discover national monuments. national parks

DedicationToPhil,whohasdiscoveredmanyparksandmonumentswithme.

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Contents

INTRODUCTION

CHAPTER1PlateTectonics

CHAPTER2MuirWoodsNationalMonument

CHAPTER3CarlsbadCavernsNationalPark

CHAPTER4JewelCaveNationalMonument

CHAPTER5DinosaurNationalMonument

CHAPTER6PetrifiedForestNationalPark

CHAPTER7GrandCanyonNationalPark

CHAPTER8LassenVolcanicNationalPark

CHAPTER9CratersoftheMoonNationalMonumentandPreserve

CHAPTER10

DevilsTowerNationalMonument

CHAPTER11GreatSandDunesNationalParkandPreserve

CHAPTER12WhiteSandsNationalMonument

CHAPTER13DeathValleyNationalPark

CHAPTER14DenaliNationalParkandPreserve

CHAPTER15BuckIslandReefNationalMonument

GLOSSARY

RESOURCES

INDEX

GLOSSARY

acids: acids are chemical compounds that taste sour. Examples are vinegar,lemonjuice,andhydrochloricacid.

adapt:achangeinanorganismthatmakesitbettersuitedtoitsenvironment.

adaptation:theprocessinwhichananimalorplantchangesinordertosurviveinitsenvironmentoveralongperiodoftime.

airpressure:theamountofpressureinanypartoftheatmosphere.Airpressurecanforceairtorushoutofsmallopeningsasitchanges.

algae:atypeofplantthatlivesinthewateranddoesn’thaverootsorleaves.

alluvial fans: huge areas of sediment that form aprons, or fans, at the base ofdesertmountains.

alpine:landhigherinelevationthanwheretreescangrow(thetreeline);whereitistoocoldandwindyfortalltrees.

altitudesickness: sickness fromgainingaltitude tooquicklyor fromstayingathighaltitudesforalongtime.Itcausesafluidbuild-upinthelungsandcanbedeadly.

archaeologist: someonewho studies ancient cultures by studyingwhat they’veleftbehind.

ArcticCircle:theimaginarylinearoundtheearth,representingthepointinthefarnorthwhere,atcertaintimesofyear,thesunneversetsorneverrises.

argongas:anodorlessgas.

asthenosphere:thesemi-moltenmiddlelayeroftheearth.

atom: the smallest particle of matter that cannot be broken down withoutchanging the particle’s properties. Everything on the earth ismade of variouscombinationsofatoms.

aurora borealis: lights in the night sky that occur because of the interactionbetweenradiationfromthesunandtheoxygenintheatmosphere.

bacteria:asingle-celledorganism.

basalt:atypeofrockthatformsfrommagmadeepintheearthflowingontotheearth’ssurface.

basalticlava:lavathat,whencooled,becomesbasalt,agrayishrock.

basin: a natural depression in the surface of the land, oftenwith a lake at thebottomofit.

bleaching: thelossofalgaefromcoraltissues.Itcanbecausedbywaterthat istoowarmorcold.

botanists:scientistswhostudyplants.

calcite:acommonmineralmadeofcrystallizedcalciumcarbonatethatisamajorpartoflimestone.

caldera:alargecratercausedbytheviolentexplosionofavolcano.

canopy:theuppermostlayerofaforest,formedbythecrownsoftrees.

canyon:adeepvalleywithsteeprockwallscutbyariver.

carbon dioxide: a gas formed by the rotting of plants and animals andwhenanimalsbreatheout.

carbonicacid:aweakacidformedwhencarbondioxidedissolvesinwater.

cave:anaturalundergroundopeningconnectedtothesurfaceandlargeenoughforapersontoenter.

cavern:averylargecaveorsystemofinterconnectedcaves.

coastal redwood: one of three species of redwood trees currently living.Redwoodsareknownforbeingthetallestlivingthingintheworldandfortheirreddishcolorbark.

ColoradoRiver:theriverthatcarvedtheGrandCanyonandflowsatitsbottom.

condense:whenwatervapor—agas—changesbackintoliquidwater.

continental:relatingtotheearth’scontinents.

convergentboundary:wheretwoplatescometogether.

crater:abowl-shapeddepression,inthetopofavolcaniccone.

crevasse:alargecrackinaglacierorindeepsnow,fromafewfeettohundreds

offeetdeep.

crown:thetopofatree,includingbranchesandleaves.

crust:theearth’souterlayer.

crystallize:toformintoarockwithacrystalshape.

decay:torotordecompose.

dendrochronology:thescienceofdatingusingtreerings.

divergent boundary: where two plates are moving in opposite directions,sometimes calleda rift zone.Newcrust formsatdivergent zones frommagmapushingthroughthecrust.

dormant:sleeping,ornotgrowing.

draperies:thin,wavysheetsofspeleothemsthathangdownlikecurtains.

drought:periodofdryweather.

dunefield:alargeareaofsandblownbywindintodunes.

earthquake: shaking anddisturbingof the earth, often violently,whichoccurswhentwoplatesontheearthslideunderandaboveeachother.

ecosystem: a community of plants and animals living in the same area andrelyingoneachothertosurvive.

element:asubstancethatismadeupofatomsthatareallthesame.

elevation:ameasurementofheightabovesealevel.

embryo:adevelopingplantoranimalbeforeitsproutsorisborn.

enzymes:proteinsproducedbycellstoperformspecificfunctionssuchaskillingbacteriaorfightingoffdisease.

erode:towearawaybyweatherorwater.

erosion:thegradualwearingawayofrockbywater,glaciers,andwind.

evaporation:whenaliquidturnsintoavapororgas.

evaporite: a mineral that has formed by the evaporation of water, leavingdissolvedmineralsbehind.Examplesaresalt,gypsum,andcalciumcarbonate.

fissure:acrackinthesurfaceoftheearth,fromwhichmagmacanerupt.

fossil:theremainsortracesofancientplantsandanimals.

fossilization:theprocessofbecomingafossil.

fumarole:aventthatemitshotgases.

genes: information in the cells of living things that determine traits of anorganism,suchashaircolor.

geologist:ascientistwhostudiesrocksandminerals.

ginkgotree:atreethatexistedInNorthAmericaduringthetimeofdinosaurs.

glacialtill:depositsofrocksmadeattheendofaglacier.

glacier:abodyoficethatslowlymovesdownslopeduetogravity.

gypsum:amineralthatisfoundinseawater,whichcanformlargedepositswhentheseaevaporates.

habitat:theenvironment.

hexagonal:six-sided.

hibernaculum:aplacewhereanimalshibernate.

hotspot:anareawherehotmagmarises,usuallyinthemiddleofaplate.

hydrochloricacid:astrongacidthateatsawayatwhateverisinit.

igneous rock: rock that forms from magma cooling and solidifying. Igneousrocks can form either beneath the surface of the earth or on the surface asvolcanicrocks.

inorganic:fromsomethingnotliving.

invertebrate:ananimalwithoutabackbone.

joint:alargecrackinarock.

KaibabUplift:adome-shapedareathroughwhichtheGrandCanyonpasses.

lahars: hugemudflows that form from lava and ashmixingwithmelted snowandrain.Theycanwipeouteverythingintheirpath.

lava:magmathathasrisentothesurfaceoftheearth.

life zones: regions of plant and animal communities based on climate andtemperature.FiveofthesevenlifezonesinNorthAmericaarerepresentedinthe

GrandCanyon.

limestone: a type of rock consisting mainly of calcium that comes from theremainsofseaanimals.

lithosphere: the rigid outer layer of the earth that includes the crust and theuppermantle.

magma:partiallymeltedrockbelowthesurfaceoftheearth.

microbe:averysmalllifeform.

microorganism:anorganismsosmallthatyouneedamicroscopetoseeit.

minerals:inorganicsubstancesthatarefoundinthegroundandinrocks.Notananimalorplant.

mudstone:asedimentaryrockmadeofclayormud.

musher:leaderofasleddogteam.

mutation:achangeinagene.

oceanic:inorfromtheocean.

old-growthforest:aforestthathasnothadamajordisturbancelikelogging,ora large fire.Old-growth forests have large live and dead trees, fallen, decayingwood,andvariouslayersofvegetation.

organism:somethingliving.

ornithischiandinosaurs:plant-eatingdinosaurswithbeaks.

paleontologist:ascientistwhostudiesfossils.

petrifaction: the process in which the material in living cells is replaced bycrystals,turningtostoneovertime.

petroglyph:arockcarving.

pictograph:animagepaintedontoarock.

plankton:smallplants,animals,orlarvaethatfloatfreelyintheocean.

plate tectonics: the theory thatdescribeshow theplatesmoveacross theearthandinteractwitheachother.

plates:huge,moving,interconnectedslabsoflithosphere.

playa:adriedlakebed.

poacher:apersonwhohuntsillegally.

polyp: a small invertebrate animal that often makes a calcium carbonateskeleton.Polypsusuallyliveincolonies,andtheirskeletonsformcoralreefs.

pyroclasticflows:high-speedavalanchesofhotash,rockfragments,andgasthattravelonacushionofcompressedairupto150milesperhour.

radioactivedecay:theprocesswherecertainelementsloseparticlesandbecomeadifferentelement.

radiometricdating:amethodofdeterminingtheageofrocks.

rainshadow:anareaonthedownwindsideofamountainrange.Whenwindsandcloudspassovermountainsitrains,leavinglittlemoisturefortheotherside.

rate:speedofsomething.

riftzone:anareawheretheearth’scrustispullingapart.

rifting:whenthelithospheresplitsapart.

runoff:minerals, chemicals and other remnants from farms and factories thatcollectinriversandlakesandeventuallyreachtheocean.

saltpan:aflatareaofgroundcoveredwithsaltandotherminerals.

saltation:thebouncingmovementofsandgrainscausedbywind.

sanddunes:aridgeofsandcreatedbythewind.

sandstone:asedimentaryrockmadeofsand-sizemineralorrockgrains.

sauropod:large,four-leggedplant-eatingdinosaurswithlongnecks,smallheadsandbrains,andlongtails.

scientific method: forming a hypothesis, or explanation for why somethinghappened,thentestingthathypothesisandrevisingitbasedonevidence.

sealevel:theleveloftheocean.

sediment:looserockparticles.

sedimentary rocks: rocks formed from the compressionof sand,mud, ash, orotherrockfragments.

silica:achemicalfoundinsandandquartz.

solution:afluidwithasubstancedissolvedinit.

species: adistinctkindoforganism,witha characteristic shape, size,behavior,andhabitatthatremainsconstantfromyeartoyear.

speleothem:adistinctivecaveformation,suchasastalactite.

stalactite:acaveformationthatlookslikeaniciclehangingfromtheceiling.

stalagmite: a cave formation projecting from the floor, often underneath astalactite.

subduct:whenonetectonicplateslidesunderneathanothertectonicplate.

tectonicplates:huge,movinginterconnectedslabsoflithosphere.

territory:aregionthatisn’tastateorprovince,butisstillpartofacountry.

TranscontinentalRailroad:arailroadbuiltacrosstheUnitedStatesinthe1860sthatfosteredthewestwardmovementofpeople.

transformboundary:wheretwoplatesslideagainsteachother.

vertebrae:backbones.

viscous:howeasilyasubstanceflows.Honeyisveryviscous;waterisnot.

volcano: a vent in the earth’s surface, through which magma, ash, and gaseserupt.

WesternHemisphere:thehalfoftheearththatincludesallofNorthandSouthAmerica.

whiteout:snowsquallssoheavyyoucanonlyseeafewfeetinfrontofyou.

zooxanthellae: blue-green algae that live in the tissue of coral polyps.Zooxanthellae contribute nutrients to the coral, and in return get a protectedplacetoliveinthesunlight.

NATIONALMONUMENTSNATIONALPARKSLOCATIONS

Alaska

DenaliNationalParkandPreserveArizona

GrandCanyonNationalPark PetrifiedForestNationalParkCalifornia

Death Valley National Park Lassen Volcanic National Park Muir WoodsNationalMonumentColorado

DinosaurNationalMonument GreatSandDunesNationalParkandPreserveIdaho

CratersoftheMoonNationalMonumentandPreserveNevada

DeathValleyNationalParkNewMexico

Carlsbad Caverns National Park White Sands National Monument SouthDakota

JewelCaveNationalMonumentU.S.VirginIslands—St.Croix

BuckIslandReefNationalMonumentUtah

DinosaurNationalMonumentWyoming

DevilsTowerNationalMonument

IntroductionOURNATIONALTREASURES

WhatdotheGrandCanyon,thePetrifiedForest,MuirWoods,andCarlsbad Caverns have in common? They are all places declarednationalmonuments—andtheyareamazingnaturalwonders.The United States has 93 national monuments (and counting!). Eachcelebrates an important andunique facet ofAmerica.Nationalmonumentscan be sites of ancient Native American cultures. They can be battlefields,forts, or remarkable structures built to honor important Americans.Manynationalmonumentscelebrateandprotectnaturalphenomena,createdbytheforcesofwind, fire,water,and time.Thisbook focuseson this lastgroup—someofthemostamazingnaturalsitesinourcountrythathavebeennamednationalmonuments.You’ll learnabout the forces that shaped theseplaces,and even tryout someprojects and experiments to learn for yourself abouttheprocessesatwork.

TIMELINEJuly 16, 1790: District of Columbia authorized, including National CapitalParks,NationalMall,WhiteHouse

April20,1832:HotSpringsReservation,Arkansas(redesignatedHotSprings

NationalParkin1921)

March1,1872:YellowstoneNationalPark,Wyoming,Montana,andIdaho

March 3, 1877: Statue of Liberty,NewYork, Erected (designated aNationalMonumentin1924)

October1,1890:YosemiteNationalPark,California

June8,1906:AntiquitiesAct

September24,1906:DevilsTowerNationalMonument,Wyoming

December 8, 1906: Petrified Forest National Monument, Arizona(redesignatedaNationalParkin1962)

May 6, 1907: Cinder Cone National Monument and Lassen Peak NationalMonument, California (incorporated in Lassen Volcanic National Park in1916)

January9,1908:MuirWoodsNationalMonument,California

January11,1908:GrandCanyonNationalMonument,Arizona(incorporatedinGrandCanyonNationalParkin1919)

DeathValley

HOWALANDSCAPEFORMSThere are many factors that go into forming the beautiful and interestinglandscapesinthenationalmonumentsbutthebasicshapeofthelandisformedbyhugeearthprocesses.Didyoueverwonderhowmountainsform?Giantplatesof theearthcollidewithandseparate fromeachother.Thispushessomeareashigher—likemountains—andsomeareaslower—likevalleys.Themovementsof

the plates, called plate tectonics, also cause volcanoes to erupt and oceans toform.We’lllearnallaboutplatetectonicsinthenextchapter.

THEUNITEDSTATESHAS93NATIONALMONUMENTS.

Landformsandtheirpositionontheearth’ssurfaceaffecttheclimate.DenaliNationalPark,whichiswayupnorthinAlaska,hasglaciersbecauseitissofarnorthandiscold.DeathValley,ontheotherhand, ishotanddrybecauseit issurroundedbymountainsthatblockcloudsfromforming.Sothereislittlerainthere.Eventheplantsandanimalsofanareachangeandaffectthelandscape-thegiant trees inMuirWoodscreateanenvironment inwhichwholeworldsexist200feetintheair!

Eventhougheachofthenationalmonumentsdiscussedhereisknownforoneor twooutstanding features, those featurescameabout fromacomplexwebofinteractions.Thefeaturesmakethembeautiful,butincrediblyinterestingaswell.

NATIONALMONUMENTORNATIONALPARK?There is a difference between national monuments and national parks. Ingeneral,nationalmonumentsare smallerandprotectonlyonemajor resource.National parks are usually fairly large in area. They are set aside because of avarietyofoutstandingscenicfeaturesornaturalphenomena.Anotherimportantdifference is who decides what becomes a national park and what becomes anational monument. National parks can only be designated by Congress.National monuments can be designated by Congress or the President.Monumentsareusuallydesignatedby thePresident, though,becauseheorshecan do it without going through the lengthy process of getting Congressionalapproval.

MANYNATIONALMONUMENTSANDPARKSCELEBRATEANDPROTECTNATURALPHENOMENA,CREATEDBYTHE

FORCESOFWIND,FIRE,WATER,ANDTIME.

Presidents have the authority to designate nationalmonuments through theAntiquitiesActof1906.ThisactwasestablishedbyCongresstoprotectmostlyprehistoric ruins, called “antiquities.” President Theodore Roosevelt also usedtheAntiquitiesActtodesignatemonumentsfortheirscientificandscenicvalue.

HenamedDevilsTower,Wyoming,thefirstnationalmonument,andhediditbecauseofitsnaturalbeautyandscientificinterest.

Thisbooklooksatfourteenofthenationalmonuments,someofwhichwerelater designated national parks. These fourteen represent a huge variety ofnaturalprocesses—fromvolcanoestoglaciers,andeverythinginbetween.

PresidentTheodoreRoosevelt

TIMELINEFebruary7,1908:JewelCaveNationalMonument,SouthDakota

October4,1915:DinosaurNationalMonument,ColoradoandUtah

August25,1916:NationalParkServiceAct

October 25, 1923: Carlsbad Cave National Monument, New Mexico(redesignatedCarlsbadCavernsNationalParkin1930)

May2,1924:CratersoftheMoonNationalMonument,Idaho(redesignatedaNationalParkin2002)

March 17, 1932: Great Sand Dunes National Monument, Colorado(redesignatedaNationalParkin2004)

January18,1933:WhiteSandsNationalMonument,NewMexico

February11,1933:DeathValleyNationalMonument,CaliforniaandNevada(incorporatedinDeathValleyNationalParkin1994)

December28,1961:BuckIslandReefNationalMonument,VirginIslands

December 1, 1978: Denali National Monument, Alaska (incorporated withMountMcKinleyNationalParkinDenaliNationalParkin1980)

Chapter1

PLATETECTONICS

What is the driving force behind how the different landscapesformed inourNationalMonuments andParks—or anywhere elsefor thatmatter?Plate tectonics.This is the theory that theearth’souterlayerismadeupofinterconnectedplatesthatareconstantlymovingaround.Volcanoes,mountains,anderosionallhappenwhere theydobecauseof themovement of the earth’s plates.Togetherwith the heat from the sun, thesepowerful forces inside theearthshapeevery landscapeandecosystemonthesurfaceoftheearth.Theearthmaylooksolidandmotionlesstous,butmostof it is partly liquid, and it’s anything butmotionless.Tounderstandplatetectonics,let’slookinsidetheearth.Theearthismadeupofthreemainlayersthathavedifferentchemicalcompositionsandphysicalproperties.

THELITHOSPHEREISBROKENUPINTO12LARGEPLATESTHATAREALWAYSMOVING.

Crust:Thesolid,outerlayeroftheearth.Itisbrittle,whichmeansthatitbreakswhen put under pressure during platemotion.Oceanic crust is about 3milesthick (5kilometers)andcontinental crust is about19-22miles thick (30 to35kilometers).

Mantle:Thelayerbelowthecrust.Itishotteranddenserthanthecrustbecausetemperatureandpressureinsidetheearthincreasethedeeperyougo.Theoutermantleissolidandcanbreak.Togetherwiththecrust,itformsthelithosphere,orthehardouterlayeroftheearth.Belowthatisalayerinthemantlecalledtheasthenosphere.Itispartiallymoltenandcanflowslowlywithoutbreaking—abitlikeSillyPutty.

Core:Thecenteroftheearthismadeofironandnickel.Theinnercoreissolidbecausethepressureissogreat,andtheoutercoreisliquid.Thecoreisalmostashotasthesun—about9,000degreesFahrenheit(5,000degreesCelsius).

THEEARTH’SPUZZLEThehardouterlayeroftheearthisn’tjustonesolidlayer,though.It’sbrokenupintoabout12largesections,calledplates.Mostoftheplatesarepartoceanicandpart continental. For example, theNorthAmericanPlate includesnearly all ofNorthAmericaandthewesternhalfoftheAtlanticOcean.Theplatesfittogetherlikeajigsawpuzzle.

Temperature differences in the asthenosphere cause molten rocks to movearoundinhuge,earth-sizecurrentsthatmovetheplatesofthelithosphereabove.

The plates are always moving—somewhere between 1 and 6 inches per year.Theyarelikesolidraftsfloatingonthegooeyasthenospherebelowthem.

WORDSTOKNOWplatetectonics:thetheorythatdescribeshowtheplatesmoveacrosstheearthandinteractwitheachother.

plates:huge,moving,interconnectedslabsoflithosphere.


oceanic:inorfromtheocean.

continental:relatingtotheearth’scontinents.

lithosphere: the rigidouter layerof the earth that includes the crust and theuppermantle.

asthenosphere: the semi-molten middle layer of the earth that includes thelowermantle.

ONTHEEDGEVolcanoesandearthquakesdon’t justhappenbycoincidence.Thereare lotsofvolcanoesaround the rimof thePacificOcean,butnoneare inKansas.That’sbecause most of the action happens where one tectonic plate meets another.

Therearethreedifferentkindsofplateboundaries.

DivergentPlateBoundaries:Hotmaterialrisesfromtheasthenosphere,causingtheplatesinthelithosphereabovetomoveapart.Asthelithospheresplitsapart,calledrifting,themoltenrockunderneathpushesoutandsolidifiestoformnewrocks.Nearlyalloftheearth’snewcrustformsatdivergentboundaries,andmostof them are under the ocean. However, one place where rifting occurs in themiddleofacontinentisatCratersoftheMoonNationalMonument, inIdaho.Sometimes rifting in a continent causes the crust to pull apart somuch that ashallowseaforms.Geologiststhinkthat’swhatishappeningintheRedSeaalongEastAfrica,andthateventuallyitwillbecomeamajorocean.

Convergent Plate Boundaries: What happens when two plates collide? Thatdependsonwhatkindof lithosphere theplates aremadeof.Whenanoceanicplate and a continental plate collide, the oceanic plate subducts, or goesunderneath the continental plate because it is denser. It sinks into theasthenosphere, and actually pulls the rest of the plate behind it. The heat andpressureintheasthenospheremeltsthesubductedlithospheretoformmagma.That magma rises to the surface, creating volcanoes. Lassen Peak in LassenNational Park, and Mt. St. Helens are volcanoes that were caused by theconvergenceoftwoplates.Infact,there’saringofvolcanoesaroundthePacificPlate called the Ring of Fire. It was formed because of the Pacific Platesubductingbeneathotherplates.

If one continental lithosphere collides with another, then they both buckleupwards, formingmountains.That’swhat ishappening rightnowbetween theIndianPlateandtheEurasianPlate,causingtheHimalayaMountainstoform.

TransformPlate Boundaries: At transform plate boundaries, the plates grindagainsteachotherastheymovesidebyside.Astheplatesmovepasteachotherthey sometimes rapidly slip, releasing a huge amount of energy, giving a biglurch,or earthquake.TheSanAndreasFault inCalifornia is a transform fault,andcausesmanyofCalifornia’searthquakes.

Anotherplacewherethere’sgeologicactivityiscalledahotspot,eventhoughit isn’t on the edge of a plate. Hotspots are small, extremely hot regions thatusuallyoccur inthemiddleofaplate.Hotmaterial,probablyfromdeepinthemantle,makes itswaytothesurface.TheHawaiianIslandshaveformedasthePacific Plate slowlymakes its way over a hotspot in themiddle of the PacificPlate.

GIANTCONVEYORBELT

GIANTCONVEYORBELTThe movement of the plates acts a bit like a conveyor belt. At divergentboundaries, magma pushes through, cools, and forms new crust. Thelithosphereislikearigidboard,though,andastwoplatesmoveapart,theotherendofeachplatecollideswithother lithosphere.At thecollision,oneplate issubducted,orpushedunder,andmelts.Lithosphereiscreatedononeend,anddestroyedonanother.

THELITHOSPHEREISBROKENUPINTO12LARGEPLATESTHATAREALWAYSMOVING.

WORDSTOKNOWdivergent boundary: where two plates are moving in opposite directions,sometimescalledariftzone.Newcrustformsatdivergentzonesfrommagmapushingthroughthecrust.


convergentboundary:wheretwoplatescometogether.



transformboundary:wheretwoplatesslideagainsteachother.

hotspot:anareawherehotmagmarisesinasmallarea,usuallyinthemiddleofaplate.

MAKEYOUROWNEARTH

SUPPLIES

mixingbowlandspoon

1cuppeanutbutter

1cupsugar

flour,asneeded

chocolatechips,about½cup

jam

butterknife

microwave-safebowl

potholders

waxpaper

coconutflakes

1Mixthepeanutbutterandsugartogetherinthemixingbowl.Addflouruntilitformsasoft,butfirmdough.Formthedoughintoballsaboutoneinchacross.

2Cuttheballsinhalfandscoopoutthecenterofeachhalf.Usingtheknife,filltheholeswith jam, andplace a chocolate chip inonehalfof eachof theballs.Thenputthetwohalvesbacktogether.

3Withanadult’shelp,melttheremainingchocolateinthemicrowave.Removethebowlfromthemicrowaveusingpotholders.Rolltheballs inthe ;chocolateandplaceonthewaxpaper-becareful,thechocolateishot!

4Rolltheballsinthecoconut.Cutoneopentolookatyourlayers,and…yum!Whoknewrockscouldtastesogood?

What’sHappening?Theearthiscomposedoflayers.Here’swhatyourconcoctionrepresents:

Chocolatechip=Inner,solidcore

Jam=Outer,liquidcore

Peanutbuttermixture=Mantle

Outerchocolatelayer=Uppermantle(partofthelithosphere)

Coconut=Crust(alsopartofthelithosphere)

YOUMIGHTHAVEHEARDOFTHEEARTH’SPLATESBEINGSECTIONSOFTHEEARTH’SCRUST.THAT’SPARTLY

CORRECT.THETECTONICPLATESAREMADEOFTHECRUSTANDTHEUPPERMANTLE,WHICHTOGETHERARECALLEDTHELITHOSPHERE.BUTMOSTPEOPLEJUSTCALL

ITTHECRUSTBECAUSEIT’SEASIERTOREMEMBER.

Chapter2

MURWOODSNATIONALMONUMENT

Silent.Still.MuirWoodsisaplaceapart.Thefirstthingsyounoticeare the huge coastal redwood trees—the tallest living things onearth.Theirtrunksseemtoriseforever,untiltheyfinallybranchtocreateanalmostsolidcanopyofbranchesandleavesabove.Ontheground,fallen,rottingtreesswarmwithladybugsorotherinsects.If you look hard enough, you can probably find a deliciously disgusting_banana slug. Steller’s jays, bright blue, break the silence with raucouscawing,andthepungentsmellofbayleavesfromtheBayLaurelfillstheair.Butifyou’reluckyenoughtoevervisitMuirWoods,thegiantredwoodsarewhatyou’llrememberfortherestofyourlife.

REDWOODSCANLIVEUPTO2,200YEARS,ANDMAYBELONGER!

WORDSTOKNOWcoastal redwood: one of three species of redwood trees currently living.Redwoodsareknownforbeingthetallestlivingthingintheworldandfortheirreddishcolorbark.

old-growthforest:a forestthathasnothadamajordisturbance like logging,ora large,devastating fire.Old-growth forestshave large liveanddead trees,fallen,decayingwood,andvariouslayersofvegetation.

condense:whenwatervapor—agas—changesbackintoliquidwater.

crown:thetopofatree,includingbranchesandleaves.

HOWDOREDWOOOSGROWSOTAIL?Fora tree togrowvery tall ithas to live a long time.So ithas toprotect itselffrom fire, disease, and wind. A tree also needs water to survive.When a treegrows extremely tall, it’s hard for enough water to be pulled from the roots,throughitsverylongtrunk,anduptotheleavesinitstop.

BANANASLUGSWhat’sbrownandyellowandsuper-slimyallover?Arottingbanana?Nope.Abananaslug!They’relikeasnailwithouttheshell,andcangrowuptoabout

10incheslong.Theylovethecool,moistforestfloorwheretheredwoodsgrow.Theirthick,gooeylayerofpoisonousslimeprotectsthemagainstpredatorsandhelpsthemclimbtrees.Thentheycandropdownquicklyusingalongstringofslime—ewwww!!!! Slug slime is one of the best natural glues, but so farresearchershaven’tbeenabletoreproduceit.Whoknowsthough,maybeonedayyou’lluseslugslimeforschoolprojects!

Herearesomeofthereasonsredwoodscangrowsotall:

CoastalredwoodsgrowinanarrowareaoflandalongthecoastofnorthernCalifornia and southernOregon, sometimes called the fog belt. Fog oftenrolls in off the Pacific Ocean, especially during the summer. Althoughredwoodsdon’trequirefogtogrow,itsurehelps:thetreesarebathedinfogduringthehottersummermonths,andnotasmuchwaterislostfromtheleavesthroughevaporation.Sometimesthefogissothickthatitcondensesontothetops,orcrowns,ofthetreesanddripsdownlikerain—calledfog-drip.

Agianttreeneedsgiantamountsofwater,soredwoodsgrowwherethere’slots of moisture in the soil. One of their favorite places is right next tostreamsinprotected,moistcanyons.

Bark that’sup toa foot thick!Thebarkprotects the innerpartof the treefrominsectsandthedamagingheatofafire.Italsopreventswaterloss.

Burls—clusters of buds that are dormant—can grow new branches, or awholenewredwood tree.Thesebudsbegin togrowwhen there’sbeenaninjurytoatree,suchasfromafire.

REDWOODSHAVEBEENAROUNDFOROVER200MILLIONYEARS—THAT’SWHENDINOSAURSROAMEDTHEEARTH.

COUNTINGRINGSAsa tree growsupward, its trunkalso growswider. Each spring, a layer oflight-coloredwoodcells forms justbeneath thebark, followedbydarker cellslaterintheyear.Eachringusuallyrepresentsoneyearofgrowth.Scientistsusetree rings to determine variations in temperatures and rain, and events likefires, earthquakes, volcanic eruptions, and pollution in past years. It makes

sense that plenty of moisture and a long growing season cause a very widegrowthring,whereasdroughtproducesanarrowring.Treeslivinginthesameregionhavesimilarpatternsoftreerings,soscientistscanestablishthekindsofpatternstolookforincertainyears.Thiscanhelpthemdetermine,forexample,when timbers used in ancientNative American dwellings were cut down, orwhenaViking shipwasbuilt.The scienceofdatingusing tree-rings is calleddendrochronology.

WORDSTOKNOWdormant:sleepingornotactivelygrowing.

drought:periodofdryweather.

dendrochronology:

thescienceofdatingusingtreerings.

AHIDDENWORLD

A redwood has a long, straight trunk, towering as high as 250 feet (76meters)beforeitbranchesout.Peopleusedtothinkthatthecanopy,orupperlayerofaredwoodforest,wasjustabunchofbranchesandleaves.Maybeafewbirds nesting here and there.No one actuallywent up there until the 1990s,whenafewbiologistsstartedclimbingtoexplorethecanopiesofthesegiants.

What they found was astounding: a maze of intertwined branches, somegrowingstraightupparallel tothemaintrunk,somegrowingoutward.Manyofthebranchesarefusedtogethertocreateanintricatenetwork,likeavirtualfloor.Inthislabyrinthisanamazingecosystemwith:

Epiphytes, or plants that grow on other plants. Hundreds of differentspecies are everywhere, including ferns, moss, lichens, other small trees,andevenhuckleberrybushes.

Massesofsoilformedfromthetreedecomposing—sometimesasmuchasthreefeetthick,completewithearthworms!

Smallcrustaceanscalledcopepodsthatusuallyliveintheoceanorstreams.

Salamandersthatlivetheirentirelifeinthetreecanopy.

Blackenedholesinthetrunksandbranches,calledfirecaves,formedwhenfirespassthroughthearea.

LOOKOUTBELOW!Muir Woods isn’t the only place where old-growth redwood forests areprotected.SteveSillett andMarieAntoinearebotanistswho studyold-growthredwood forests all over northernCalifornia.Theyhelped to pioneer climbinginto thecrownsof thesehuge trees, andare still findingnewwaysof climbingandstudyingthem.Theywearsoftshoesandusesoftropestoavoiddamagingthetrees.Onceupinthecrown,theyspendmostoftheirtimehanginginmidairsuspended by the ropes. They only step on branches when they have to, andthen,verydelicately.

Climbing a 300-foot-plus (91-meter) tree isn’t for the timid or the careless.Onesmallmistake,likenotattachingaropejustright,cancostyouyourlife.Afallingbranchcankill.And thenetworkofbranches is socomplicated that it’sactuallypossibletogetlostforawhile.EvenSteve,whoisoneofthebesttall-treeclimbersintheworld,sometimesfeelstheterrorofimaginingafree-fall.Butheandtheotherscontinuetoclimbbecauseitistheirpassiontolearnalltheycanaboutredwoods,andbecausetheywanttohelppreservethemforthefuture.

Stevespeaksformanyofhiscolleagueswhenhesays,“…thesetreeshavenovoice.Mylife’sworkistospeakforthesetrees.”

TRYTHIS!COUNTTHERINGS

Findatreestumpinyourneighborhood,preferably fromatreethatwasrecentlycutdown.Countthedarkringsstartingfromtheoldestlayersinthecenter,goingout.Thenumberofrings isaboutequaltohowoldthetreewaswhenitwascutdown.Seeifyoucanfindanothertreestump.Doyouseesimilaipatternsinthewidthoftherings?

WORDSTOKNOWcanopy:theuppermostlayerofaforest,formedbythecrownsoftrees.


species:adistinctkindoforganism,withacharacteristicshape,size,behavior,andhabitatthatremainsconstantfromyeartoyear.

botanists:scientistswhostudyplants.

WHAT’SINANAME?The land forMuirWoodswas donated byWilliam and ElizabethKent toprevent a nearby water company from taking over the area. Most of theredwoodsintheregionsurroundingMuirWoodshadalreadybeenloggedfortimber. The Kents requested that it be named after John Muir, a notedconservationistwhohelpedtopreservetheareathatbecameYosemiteNationalPark. The Sierra Club is an environmental organization founded in 1892 by

JohnMuirtoexplore,enjoy,andprotectthewildplacesoftheearth.JohnMuirwrotemanybooksaboutnatureandconservationthatpeoplestillreadtoday.

JohnMuir

FamousTreesAmericahasthetallest,themostmassive,andtheoldesttreesonEarth.

Tallest tree:Acoastal redwood like the trees inMuirWoods. It’s inRedwoodNationalParkandmeasures379feet(115meters).That’sastallas:

90kidsstandingontopofeachother.

74,516penniesstackedontopofeachother.

75feettallerthantheStatueofLiberty.

Oldest tree: A Bristlecone Pine in theWhiteMountains of California, that isover 4,789 years old. How old is that? It starting sprouting about when theEgyptiansstartedbuildingpyramids.

Most massive tree: A Giant Sequoia, another type of redwood, in SequoiaNationalPark.Itis275feet(84meters)talland36feet(11meters)aroundatthebase,andisestimatedtoweighabout2,500metrictons.That’sasbigas:

204Africanelephants,thelargestlandanimal.

171bluewhales,thelargestanimalevertohavelivedonEarth.

33,660grownmen!

TRANSPIRATION

1Lookcarefullyattheleaves,especiallytheunderside.Doyouseesmallholes?These are called stomata, and they allow for the exchange of gases like watervaporandcarbondioxide.

2Labelthebagsthefollowingway:

NoVaseline/sun

NoVaseline/shade

Vaselineontop/sun

Vaselineonbottom/sun

3 Coat the leaves with Vaseline according to the labels, place in thecorrespondingbag,andsealthebag.

4 Place the bags in the sun or shade, according to the labels, andwait for anhourortwo.Whatdoyouthinkwillhappen?

5Lookatthebagsafteranhourortwo.Doyouseeanydifferencefrombefore?Whatdoyouthinkcausedthis?Whyaretheredifferencesbetweenthebags?

What’sHappening?Thebagshavewatervaporthathascondensedonthe insideof thebags.Ithascome from the leaves, which transpire, or release, water vapor through theirstomata. Stomata are usually on the bottoms of leaves. Where Vaseline wascoatingthestomata, theycouldn’treleasewatervapor,soyouprobablysee lesswaterinthebagwhereyoucoatedVaselineontheundersideoftheleaf.Youalsoprobablysaw ,water inthebagplaced inthesun.That’sbecausethesunheatsthebagandleaf,causinganincreaseintranspiration.Normally, thatwaterwillevaporatefromalivetree,buttheplasticbagsealsthewaterin.

THEREUSEDTOBEABOUT2MILLIONACRESOFOLD-GROWTHREDWOODFORESTCOVERINGTHECOASTSOFCALIFORNIAANDOREGON.MOSTISGONENOW.ONLY

ABOUT4PERCENT,OR90,000ACRES,ISLEFTUNTOUCHED.MUIRWOODSISABEAUTIFULEXAMPLEOFOLD-GROWTH

REDWOODFOREST.

SUPPLIES4zipperedplasticbaggies

markerorlabelsandpen

4leavesfromaliveplantortree

Vaseline

asunnyday

magnifyingglass(optional)

Chapter3

CARLSBADCAVERNSNATIONALPARK

ChineseTheater

CarlsbadCavernEntrance

Walking into Carlsbad Cavern through its natural entrance isunsettling.Asyouapproachtheopeningtothecave,thepathpasses

throughthegrasslandanddesertshrubsofNewMexico.It’salmostalwayssunnyanddry,andinthesummeritmightbe100degreesFahrenheit(38degreesCelsius)outside.Butasthepathwindsintothelargedarkhole,itseemstosimplyendindarkness.Asyoudescendintothecavern,youknowthatyouaregoingwherehumansarenotmeant to live. It is adark and silentplace.Alwaysdamp, always56degrees F (13 degrees C). Soon enough, though, as you pass hundreds ofstrange and gorgeous rock shapes, the silence is calming. You feel thatperhapstherockitselfisalive.Inaway,itis.Theseshapeshave“grown”dripbydrop.

DripbyDrop:TheMakingofaCavernRockseemssolid,doesn’t it?Buteventhehardestrockcanbewornawaywithenough time. Some kinds of rock—like salt—can even dissolve in water.Limestoneisarockthatdissolvesinwater,butonlyifthewaterisslightlyacidic.Lemonjuiceandvinegarareacids,soifyouaddedafewdropsoflemonjuicetowater itwouldbe slightly acidic.All rainfall isnaturally slightly acidicbecausecarbondioxideintheairreactswithwatertoformcarbonicacid.

Limestone oftenhas cracks in it, and rainwater seeps into these cracks.Thecarbonicacidintherainwaterslowlydissolvestherock,makingthecrackswider.Insomecavesastreamcantravelthroughthelimestoneuntilitfindsanoutlet,erodingevenmorerockalongtheway.Eventually,partoftheroofcancollapse,whichformslargercaverns.

Questions,Questions

Upuntilthe1970s,everyonethoughtthatCarlsbadCavernsformedinthisway.There were some nagging questions about Carlsbad, and like your mothernaggingyoutocleanupyourroom,thesequestionsdidn’tgoaway.Howdidthecaverns—especiallytheBigRoom—growsolarge?Whyisn’tthereanyapparentplacewhere thewater had entered or left the caverns? If flowingwater didn’terode the limestone,whatdid?Howdid thehugeblocksofgypsumgeton theflooroftheBigRoom?

WORDSTOKNOWcave: a natural underground opening connected to the surface and largeenoughforapersontoenter.


limestone:atypeofrockthatoftenformsfromtheshellsofmarineanimals.

acidic: acids are chemical compounds that taste sour. Examples are vinegar,lemonjuice,andhydrochloricacid.

carbondioxide: agas formedby therottingofplantsandanimalsandwhenanimalsbreatheout.

carbonicacid:aweakacidformedwhencarbondioxidedissolvesinwater.


TRYTHIS!

Puta fewspoonfulsof salt intoaglassandstir in just enoughwarmtapwateruntil all of the saltdissolves.Did the salt reallydisappear?Let theglasssitinawarmplacelikeawindowsillforafewdaysuntilthewaterhasevaporated.Isthereanythingleftbehind?

This last question was especially hard to answer because gypsum, like salt,easilydissolvesinwater.Youdon’tusuallyseemuchgypsumincavesbecauseallthatseepingandflowingwaterdissolvesthegypsumandcarriesitoff.

Scientists did what they usually do when the facts don’t add up. Theyproposedother theories.One ideawasespecially interesting: that the limestonewas dissolved by sulfuric acid. When sulfuric acid reacts with limestone, thelimestonedissolves,andgypsumformsfromthereaction.Sulfuricacidismuchstrongerthancarbonicacidanddissolvesabouteighttimesasmuchlimestone.But this idea raised other questions. Sulfuric acid is no commonly found innature.

Sowherecouldithavecomefrom?Thisiswhatscientiststhinkhappened:

1.Deepunderground,belowthefloorofthecavern,thereareoilandnaturalgasdeposits. Millions of years ago bacteria living there ate the oil (yum!), whichproducedhydrogensulfidegasthatroseupthroughthelimestone.

2.Thehydrogensulfidecombinedwithoxygenfromrainwaterseepinginfromabovetoformsulfuricacid.

3. Sulfuric acid reacted with the limestone and dissolved huge amounts of it,formingthecavernsandleavinggypsum.

It tookmanyyears andmany scientistsworkingand sharing information tofigure all of this out. Once they figured out the process at Carlsbad Caverns,though, it was easy to see evidence of the same process happening at severalothercavesaroundtheworld.

WORDSTOKNOWspeleothem:adistinctivecaveformation,suchasastalactite.

stalactite:acaveformationthatlookslikeaniciclehangingfromtheceiling.


HISTORYOFCARLSBADThelimestoneinCarlsbadwasdepositedabout250millionyearsago.Itusedtobeareef,nottoodifferentfromthecoralreefatBuckIslandReefNational

Monument.Itcontainsfossilsofsnails,sponges,andotherseacreatures.Overtime,sulfuricaciddissolvedhugeamountsoflimestone,formingtheBigRoomandothercaverns,and leavingbehindbigblocksofgypsum.About3millionyears ago, rainwater seeping through the limestone deposited the lovelystalactites, stalagmites, andother speleothemsbydripping.MuchofCarlsbadCavernismostlyinactive,andnotformingstalactitesandstalagmites,becausethere’s so little rainfall in the area now. There’s not enough water seepingthroughtherocktodripintomostofthecaverns,soonlyabout10percentoftheformationsarestillactive.

Popcorn,Pearls,andDraperiesOncecavernsform,caveformationsofallshapesandsizescandevelopthatlookliketeeth,columns,curtains,pearls,andbeards!Thesecaveformationsarecalledspeleothems. As rainwater seeps through limestone and dissolves it, thelimestonedoesn’tdisappear—it’s just in thewater.When thewaterdrips fromtheceilingofacave,avery smallbitof limestone is leftbehind.Dripbydrop,huge speleothems form. The kind of speleothem formed mainly depends onwhetherthewaterdrips,trickles,orseepsintothecave.

Stalactites:growwherewaterdripsfromtheceiling.

Stalagmites:growwherewaterdripsontothefloor.

Columns:whereastalactiteandstalagmitejoin.

Draperies:growwherewaterrunsdownaslantedceilingorwall.

Flowstone:growswherewaterflowsoverthesurfaceofwallsorfloors.

Pearls:growinpoolsofcalcite-richcavewater,justlikearealoysterpearl—layeruponlayerslowlybuildingaroundagrainofsand.

Beards:growfromwatercontainingdissolvedgypsum.

Popcorn:clustersthatlooklikepopcorn,orgrapes,foundonceilings,floors,andwallsofcaves.

LechuguinacaveAlthoughCarlsbadCavernisthebest-knowncaveinthepark,thereareatleast111caveshere, includingLechuguilla.This is thedeepest limestonecave intheUnited States—1,604 feet deep (489 meters).When people first discovered it,theyassumeditwasjustoneofmanysmallcavesinthearea.Theninthe1950s,caversheardwindroaringfromthefloorandwonderedifthereweremorecavesunderneath.Extensivecavepassageswerediscoveredunderneaththefirstsmallcave.Todayscientistscome fromaround theworld toexplore the fifth-longestcave in theworld.Thespeleothemsareamazing,with18-foot (5.5-meter)sodastraws,cavepearls,and20-foot(6-meter)hairsandbeards.

SNOTTITESARECOLONIESOFBACTERIATHATARESIMILARTOSMALLSTALACTITESBUTHAVETHE

CONSISTENCYOFMUCOUS,ORSNOT.

Itty-BittyCrittersMost life in caves is near the entrance. Plants need light to make food, andanimals need to be near plants and other animals to get their food. Butmicroorganismslikebacteriacangetitsfoodinotherways,andcanlivedeepinthecaves.

Microorganisms that live indeeppoolsofCarlsbadandothercaveshave tocompete with each other for very few nutrients, and some of them releaseenzymes tokill theothermicroorganisms.TheenzymesinonemicroorganismdiscoveredinCarlsbadCavernshavebeentestedandfoundtokillsometypesof

cancercells.Anothercanbreakdowncertainpollutants for food.Scientistsareworking to use the different properties of cave microorganisms to figure outbetterways to do lots of things, like how to produce environmentally friendlypaper.

Cavemicrobesarealsobeingstudiedtohelpfindanswersaboutwhethertheremightbeotherlifeintheuniverse.Becausecavemicroorganismsliveinextremeenvironments,usingmineralsasfood,theygiveapictureofwhatlifeonMars,orotherplaces,mightlooklike.

WORDSTOKNOWmicroorganism:anorganismsosmallthatyouneedamicroscopetoseeit.

enzymes: proteins produced by cells to perform specific functions such askillingbacteriaorfightingoffdisease.

ITCANDRIVEYOUBATTY!

EveryeveningfromApriltoSeptember,hundredsofthousandsofMexicanfree-tailed bats that live in the “Bat Cave” just inside the entrance toCarlsbadCavern swarmout to feed. It can takeup to threehours for all ofthem to come out, and most return just before dawn. They spiral out in acounter-clockwisedirection.Nooneknowswhyforsure,butitmayhavetodowiththemagneticpolesintheearthandhowthebatsfindtheirdirection.Themagneticpolesarethepointswheretheearth’smagneticfieldiscentered.Oneisinthesouthandoneinthenorth,neartheNorthandSouthPoles.

SCIENTISTSHAVEANALYZEDTHEGUANOINTHEBIG

SCIENTISTSHAVEANALYZEDTHEGUANOINTHEBIGROOMINCARLSBADCAVERN.THEYDISCOVEREDTHAT

SOMEOFTHEGUANOHADBEENONITSFLOORFOR48,850YEARS!

When the bats come out, first they findwater, then they head for breakfast.Andwhatabreakfast;alltogethertheyeataboutonetonofinsectseverynight!Whenthebatsreturntothecaveattheendofthenight,theysometimesdivefromhundredsoffeetandcangoasfastas25miles(40kilometers)perhour.

TheMexicanfree-tailedbatsmigrateeveryyearbetweenCarlsbadCavernsandMexico.Theylovethecool,darkcaveofCarlsbadforsleepingduringtheday,andthesurroundinglandscapehasplentyofbugstoeat.Aparadise.

Wheretherearebats,there’sbatpoop.Alotofbatpoop.Thepolite,scientificwordforbirdandbatpoopis“guano,”andthereusedtobethickdepositsofitintheBatCave.Inthe1800salotofbatguanowastakenandsoldtofarmersforfertilizer.Thatmusthavebeenafunjob…todaytheBatCaveisclosedtothepublictoallowthebatstosleep.

©MerlinD.Tuttle,BatConservationInternational,www.batcon.org

MAKEYOUROWNCAVERN

1Arrangethesugarcubesinstacksofvaryingheightinthejar.Makesuretheoutsideofthejarislinedwithsugarcubes.

2 Completely cover the opening of the jar with a layer of clay at least one-eighth-inchthick.Makesuretherearen’tanygaps.

3 Pokeholes in the clay,making sure theholes reach to the sugar cubes.Trypokingjustafewholesononesideofthejar,andmanyholesontheother.

4Sprayorslowlypourwateroverthetopoftheclay.Addfoodcoloringifyouwish.

5Asthewaterseepsthroughtheholes,lookatthesugarcubesthataretouching

http://www.batcon.org

thesidesof theglass jar.What’shappening?Let theexperimentsit forawhile,thenspraymorewater.Arepassagewaysforming?

What’sHappening?Thesugaractslikethelimestoneincaves.Sugardissolvesinwater,sothesugarcubesdissolvewhenthewaterdripsontothem.Withcaves,limestonedissolveswhenslightlyacidicwatercomesintocontactwiththelimestone.Or,inthecaseofCarlsbadCaverns,sulfuricacidfromdeepbelowdissolvedthelimestone.Theclayinyourexperimentdoesn’tdissolve,justlikesoilorclayovercavesdoesn’tdissolve.

SUPPLIESboxofsugarcubes

1-2poundsmodelingclay

largeglassjaroraquarium

toothpick

foodcoloring(optional)

spraybottle(optional)

Chapter4

JEWELCAVENATIONALMONUMENT

CalciteCrystals

Stalactites

JewelCavehasincrediblecaveformationslikegorgeous,sparklingcalcite crystals, intricate 11 gypsum formations, and even“balloons” that look like they might pop before your eyes. Even

thoughtheformationsaretoosofttobeconsideredtrue“jewels”orgemstones,they’reeverybitaslovely.Up until about 1960, people thought Jewel Cave was just a small cave—beautiful,butsmall.Ascaverskeptexploring,theydiscoveredthatJewelCaveisnotonlyoneofthemostbeautifulcaves intheworld,butalsothesecondlongest. And cavers aren’t finished exploring. Maybe they’ll find it’s thelongestcaveintheworld!

JEWELCAVE’S142MILES(228KILOMETERS)OF-EXPLOREDCAVEWINDAROUND,SOALLOFTHOSEMILESAREONLY

UNDERABOUT3SQUAREMILESOFSURFACEAREA.

Middle:NPSPhoto;LeftandRight:PhotosCourtesyofArtPalmer

BACTERIAHAVEBEENFOUNDINJEWELCAVETHATARESIMILARTOTHOSEFOUNDINLECHUGUILLACAVEIN

CARLSBADCAVERNSNATIONALPARK.

THEJEWELSJewel Cave formed in the classic way of limestone caves. Rainwater seepingthough the limestone rock dissolved it, forming caves and caverns over time.Later, rainwater formed the amazing jewels in the same way that otherspeleothemswerecreatedinCarlsbadCaverns.

Mixed inwith the limestone is anothermineral, calledgypsum.The seepingrainwaterpicksupbitsofgypsum,whichitthendepositsinthecaves.Gypsumformationsareverydelicate,andtheyformonlyindrypartsofthecavebecause

gypsumdissolvessoeasilyinwater.

WORDSTOKNOWcave: a natural underground opening connected to the surface and largeenoughforapersontoenter.

calcite: a commonmineral made of crystallized calcium carbonate that is amajorpartoflimestone.

gypsum:amineralcontainingcalciumandsulfur.Itcanformfromareactionbetweensulfuricacidandlimestone.



TAKEABREATHEVERY5DAYS…ANDBREATHELIKEACAVE

Jewel Cave breathes. About once every five days or so it breathes in, then itswitchesandbreathesout.Whentheairpressureishigherinsidethecavethanon the surface, air rushes out because air moves towards where there’s lowerpressure.When the pressure is lower inside, air rushes in. Sometimes that airmovesprettyfast—upto35miles(56kilometers)perhour,andyoucanhearthewindwhistling.That’snearlytwiceasfastasthefastesthumanrunner.Someofthecavesthathaveespeciallystrongwindshavenamestogowithit:HurricaneCorner,Humdinger,andDraftyManeuver.

ResearchisgoingonatJewelCavetousethedifferentairpressuresandwindtocalculatethetotalvolumeofthecave.Turnsout,thepartsofthecavethatareknownandhavebeenmappedareonlyabout3percentofthetotalvolumeofthecave.Sothatmeansthatinsteadofbeing142miles(228kilometers)long,JewelCaveisprobablythousandsofmileslong!

Researchers don’t know if they’ll be able to explore thewhole length of thecave.Itcouldnarrowtoaverysmallopeninginplaces,toosmalltogetthrough,butsofar,sogood.JewelCavecouldevenconnecttoothercavesinthearea,likeWind Cave National Park. The longest cave in the world, Mammoth CaveNationalPark inKentucky,has a known lengthof 365miles (587kilometers).

Even though Mammoth Cave still has unexplored parts too, there’s a goodchancethatJewelCavewillturnouttobethelongestknowncaveintheworld—eventually.

ONEBROWNBATCANCATCHHUNDREDSOFMOSQUITOESINJUSTONEHOUR!

BATHOTEL

Nine different species of bats live in Jewel Cave NationalMonument,it’sagreatplaceforalongwinter’snapifyou’reabat.Therearelots of different levels and temperatures to choose from, so it’s the perfecthibernaculum, or place to hibernate. It’s important that bats be leftundisturbedwhiletheyhibernate,sothemonumentacesgatesontheHistoricEntranceinthewinter.Theotherentrance,awayfromthebats,staysopen.Thehorizontalbars let thebats flyout,butpeople can’t get in.Oneof the largestknowncoloniesofTownsend’sbig-earedbat,ararespecies,hibernatesinJewelCave.

WORDSTOKNOWspeleothem:adistinctivecaveformation,suchasastalactite.

air pressure: the amount of pressure in any part of the atmosphere. Airpressurecanforceairtorushoutofsmallopeningsasitchanges.


hibernaculum:aplacewhereanimalshibernate.

SPARKLYCLEAN(OR“LINTCAMP”)Every hour, your body sheds about 60,000 skin fragments, 160 million dustparticles,20,000clothing-lintparticles,25quartsofcarbondioxidegas,and170wattsofbodyheat.Yuck.

Normallyall thatshedding isnotabigdeal,but inacave it’sabigproblem.Thedust andothermaterialspeoplegiveoff travel to allpartsof the cave anddullanddiscolor thespeleothems.Sometimes, the lintandskincells formgraymattsorevenhangfromtheceilingin“lintcicles.”Thecontaminationcanevencauseformationstoslowlydisintegrate.

Whattodo?TheNationalParkServiceplanstopreventlintfromspreadingtoall parts of the cave by putting in short rock walls along the trails and usingspecialvacuumstopickupthelint.EveryyearatJewelCave,CarlsbadCaverns,and other caves, trained volunteers come for a week of “Lint Camp.” Theycarefullycleanthelintfromcaveformationsusingtinytweezersanddrillpicks.

WORDSTOKNOWcarbondioxide: agas formedby therottingofplantsandanimalsandwhenanimalsbreatheout.

needles,beards,andspiders:variouscaveformations.

popcorn:small,knobbycalcitespeleothems.

draperies:thin,wavysheetsofspeleothemsthathangdownlikecurtains.

PhotoCourtesyofArtPalmer

WHAT’SITLIKETOGOCAVING?All of the cave exploration and mapping of Jewel Cave is done by trainedvolunteers. They share a love of being in caves and being the first humans todiscover a new passage. If you were one of those cavers, you would have toclamberoverslipperyboulders.You’dcrawlonyourbellythroughan1,800-foot(548-meter) section called the “Miseries” with spots only 7 inches high, withnameslike“CalorieCounter”and“FunnyLittleHole.”Andyou’dcampandhikein total darkness for several days at a time with only lanterns and flashlights.Cavers take the elevator down, then hike about 7 hours just to get to wherecurrentexplorationstarts.Altogethertheymapabout2miles(3.2kilometers)ofunexploredcavesinJewelCaveeachyear.

Trygoingintoaclosetatnightandturningoffallofthelights.Youcanstillprobablyseealittlebitafteryoureyesadjusttothedark.Notsoinadeepcave.Withoutthelightscaversbringwiththem,itisutterblackness.

FLOWERSANDBALLOONS

HerearesomeamazingspeleothemsyoumightseeatJewelCave:Flowers:growfromgypsum.

Balloons: these start as a speleothem that looks like cottage cheese. In somerarecases,airgetsintotheformation,and“blowsup”thespeleothemintoanair-filledballoon.

Needles, beards, and spiders, as well as dogtooth spar, nail head spar,boxwork,popcorn,anddraperies.Someofthemarestillforming.

GypsumFlower

Balloons

THEARTOFEXPLORINGCAVESISSOMETIMESCALLED“SPELUNKING,”ANDPEOPLEWHOEXPLOREARECALLED

“SPELUNKERS.”BUTUSUALLYSPELUNKERSCALL

“SPELUNKERS.”BUTUSUALLYSPELUNKERSCALLTHEMSELVES“CAVERS”ANDTHEYCALLEXPLORING“CAVING.”WHATEVERIT’SCALLED,IT’SALWAYSAN

ADVENTURE!

Top:NPSPhoto;Bottom:PhotoCourtesyofArtPalmer

MAKEYOUROWNSTALACTITES

1Findaplace todo theexperimentwhere itwon’tbedisturbed.Fill thecupswithwarmwater.StirinEpsomsaltsuntilnomorewilldissolve.

2Cutabout18 inchesof string.Tie twopaperclips toeachendandsoak thestringinoneofthecups.

3Pullthestringoutanddrapeoneendofthestringineachcup.Placethecupsabout1footapartwiththedishinbetween.Thereshouldbeaslightdrooptothestring,butdon’tletittouchthetable.

4Checktheprojecteachday.Doyouhaveanystalactitesorstalagmites?

SUPPLIES2glassesorcups

Epsomsaltsfromthepharmacy

warmtapwater

cottonorwoolstring

4paperclips

dish

WORDSTOKNOWstalactite:acaveformationthatlookslikeaniciclehangingfromtheceiling.


solution:afluidwithasubstancedissolvedinit.

What’sHappening?TheEpsomsaltsaredissolvedinthewarmwater.Thewater/saltsolutionslowlytravels down the string to the lowest point,where thewaterdripsdown.As itdripsdown,someofitevaporates,leavingthemineralsbehindtoslowlybuildupinto a stalactite. As the water evaporates from the dish, the minerals are leftbehind to form a stalagmite growing upward. A similar process is at work incaves.

Chapter5

DINOSAURNATIONALMONUMENT

Dinosaur National Monument is a landscape of gorgeous rivercanyonssetinruggeddesert.Itcontainsincrediblefossilsofplantsandanimals,includingfish,crocodiles,anddinosaurs.Hikingoneof Dinosaur’s many trails, you physically step back in time to aworldfilledwithferns,ginkgotrees,andApatosaurusdinosaurs!IlIIInthe late1800s,peoplebecamefascinatedwiththestartlingfossilsofhugereptiles that were being found. Every museum wanted a dinosaur fossil,including the Carnegie Museum in Pittsburgh, Pennsylvania. ApaleontologistnamedEarlDouglasswasaskedbythedirectoroftheCarnegieMuseumtolookfordinosaursforthemintheAmericanWest.Fewcompletedinosaurskeletonshadbeenfounduptothispoint.PhotosCourtesyofIanTurton

DINOSAURHASTWORIVERS,THEGREENANDYAMPA,WHICHHAVECUTGORGEOUSCANYONSTHROUGH

PRISTINEWILDERNESS.MANYPEOPLERAFTTHERIVERSORHIKETHROUGHTHERUGGEDDESERT.

DouglassscouredthecountrysideinnortheastUtah,whererockswereofthesametypeinwhichdinosaurshadbeenfoundelsewhere.OnAugust19,1909,hefoundeightlargevertebraestickingoutofrock.Hewrotebacktothemuseum:“I have discovered a huge Dinosaur, Brontosaurus [now known to beApatosaurus],andif theskeletonisasperfectas theportionswehaveexposed,the taskof excavatingwillbeenormousandwill costa lotofmoney,but… itwouldbethebestJurassicDinosaurinexistence.”

Excavatingthedinosaurdidprovedifficult.Douglassbuiltroadsandtunnelstotheremotesite,dynamitedtobreakloosetherock,andwrappedthefossilsinplasterforshipping.

WORDSTOKNOWcanyon:adeepvalleywithsteeprockwallscutbyariver.


ginkgotree:atreethatexistedinNorthAmericaduringthetimeofdinosaurs.


vertebrae:backbones.

NEWSPECIESOFPLANTANDANIMALFOSSILSAREFOUNDINDINOSAURNATIONALMONUMENTEACHYEAR.

INDINOSAURNATIONALMONUMENTEACHYEAR.

GettingthefossilstoPittsburghwasjustaschallenging.Ittook12wagons,24horses,and8driversin1910tomovethefirstshipmentofbones70milestoarailroad,andthenontoPittsburgh.Thatfirstshipmenthadover20tonsofrockandbones.Over13years,Douglassshippedmorethan350tons!

Thatwasnottheendofitthough,asmanymoredinosaurswerefound—andcontinuetobefound—atDinosaur.

LONG-NECKS:BIG,LONGBODYITTY,BITTYBRAINCASE

Sauropods,withlizardfeetandlongnecks,werehugedinosaurs—theSeismosauruswasperhaps150feetlong.Buttheyhadsmallheads.Lookingatthem,IyoumightwonderiftherewasabraininIthereatall!Theskullsweresothinand*fragilethatonlyadozenfromtheJurrasicperiodhavebeen found.Theyseemtohaverottedawaybefore theycould fossilize.Fromthe Cretaceous, the last period that dinosaurs lived in, no skulls from long-neckshadbeenfoundinNorthAmerica.

Until 2000, that is.That’swhen the first of four skulls from long-neckswerefound that are from a new species from the Cretaceous period. Makes you

wonderwhatelseisburiedtheretoo!

THEWORD“DINOSAUR”COMESFROMTHEANCIENTGREEKWORDSDEINOSFOR“FEARFULLYGREAT”AND

SAUROSFOR“LIZARD.”

AWALLOFBONES

In 1958, a new Visitor Center was built over the quarry so thepublic couldview the fossils.Over 1,600 boneswere left in the originalrockandputondisplayintheVisitorCenter.

FOSSILSFROMDINOSAURNATIONALMONUMENTCANBEFOUNDINMUSEUMSAROUNDTHEWORLD!

AWHOSWHOOFDINOSAURSThereare11differentspeciesofdinosaursthathavebeendiscoveredatDinosaurNational Monument so far, including a new, unnamed species discovered in2000.Thenumberofdinosaurfossilsfoundisinthethousands,ranginginsizefrom7inchesto76feet(23meters).

Apatosaurus theveryfirstskullof thisspecieswasfoundatDinosaurNationalMonument. Itwas the first skeleton found there in1909and it’salso themostcompleteApatosaurustodate.ThediscoveryprovedthatApatosaurushadaverylongtailwithaso-called“whiplash”ontheend.

Camarasaurus: a juvenile, only 15 feet long (4.5 meters), was uncovered atDinosaurin1923.Itisthemostcompletesauropodskeletoneverfound.Itsearboneswerethefirstfoundinasauropod.

AllosaurusSkull

Camptosaurusin1992,thepartialskeletonofaCamptosaurusembryo,lessthan9incheslong,wasfoundatDinosaur.

Diplodocustworareskullshaverecentlybeenfound,includingoneofajuvenile.

Allosaurus: the most common, large predatory dinosaur in North AmericaduringthelateJurassicPeriod.Ithadserrated,blade-liketeeth.

And also … Barosaurus, Ceratosaurus, Dryosaurus, Torvosaurus, andStegosaurus.

FOSSILS:FROMROAMINGTHECOUNTRYSIDETOMUSEUMEXHIBITS

How does a ferocious Allosaurus go from terrorizing smaller dinosaurs towatchingoverthehallsofamuseum?

1. To become a fossil, a dead plant or animal first must be quickly andcompletelyburied.Burialprotectstheremains.Mostplantsoranimalsthatdiearen’tburied,sotheyareeithereatenbyotheranimalsordecay.That’sthemainreasonwhywedon’tfindfossilseverywhere.

2. There are different ways fossilization can happen. Dinosaur bones aremainlypreservedbypetrifaction.This iswhenparts of anorganismare filled

withwaterthathasdissolvedmineralsinit.Themineralsgraduallyfillinthetinyspaceswheresofttissuesuchasbloodvesselswere,andhardenwiththebonetoform a fossil that still shows the structure of the remains. At Dinosaur, thedinosaurboneswerefilledwithsilica,andyoucanseethedetailedstructureofthebones.

3.The fossil-bearing sediments areburiedmoreandcompressed,becomingsedimentaryrock.Mostfossilsarefoundinsedimentaryrocks,whicharerocksthatformfromthecompressionofsand,mud,ash,orotherrockfragments.

4.Allofthistakesaverylongtime—manymillionsofyearsinfact.Afteralotmoretime,therockscontainingfossilsareexposedtothesurface.Thisgenerallyhappensbytheregionbeinguplifted,andtherocksabovethemeroding inthewindandweather.Finallysomeonediscoversoneormorefossilsinanarea.

PhotoCourtesyofIanTurton

WORDSTOKNOWsauropod: large, four-legged plant-eating dinosaurs. They typically had longnecks,smallheadsandbrains,andlongtails.

embryo:adevelopingplantoranimalbeforeitsproutsorisborn.

decay:torotordecompose

fossilization:theprocessofbecomingafossil.

petrifaction:whensomethingthatabsorbswater turnstostone,mainlyboneorwood.

silica:akindofstone.

sedimentaryrocks:rocksformedfromthecompressionofsand,mud,ash,orotherrockfragments.


5.Paleontologistscarefullydig,mostlyusingrockpicksandchiselstoexposethe fossils, and paint brushes to brush away the dust. Sometimes they use ajackhammertoremovelargepiecesofrock.Thefossilandanysurroundingrockarewrapped in a protective plaster and burlap “jacket” as they are unearthed.When the fossil and rock are completely exposed, they are shipped to alaboratoryinamuseumorschool.

6. Fossils can take weeks or months to properly prepare, and a large ordelicatefossilcaneventakeyears!Dentaltoolsandbrushesareusedtoremovebitsofrock.Specialchemicalsandglueshelpstrengthenthebone.Moldsorcastsof the fossils can be displayed, and the bones are often assembled into whatscientistsbelievetheanimallookedlike.Finally,alloftheinformationaboutthefossil isrecordedinacatalog,suchaswhereitwasfound,therocklayer itwasfoundin,andwhofounditandwhen.


WORDSTOKNOWarchaeologist:someonewhostudiesancientculturesbystudyingwhatthey’veleftbehind.

petroglyph: a rock carvingmade by pecking on a rock surfacewith anotherrockorchisel.

pictograph:animagepaintedontoarock.

THEROCKSINDINOSAURNATIONALMONUMENTSPANOVER1.1BILLIONYEARS.THEREAREMORETHANJUST

DINOSAURFOSSILSTHERE—YOUCANALSOSEEFOSSILSOFCROCODILES,LIZARDS,FROGS,SALAMANDERS,AND

TURTLES.

WHYHERE?Ifit’ssohardforfossilstoform,especiallyfromlargelandanimals,howdidallofthesedinosaurfossilsendupatDinosaurNationalMonument?Scientiststhinkthat an ancient river once flowed in this area that began drying up about 150millionyearsago.Oneof the lastplacesanimalscouldgetwaterwasDouglassQuarry, the area where Douglass first found dinosaur fossils. As the riverbeddriedup, dinosaurs andother animals died, leaving their remains in thedriedriverbed.

PETROGLYPHSANDPICTOGRAPHS

Beginning around 1,800 years ago, the Fremont people lived intheareaofDinosaurNationalMonument,cultivatingcorn,beans,and squash. They disappeared around 700 years ago, perhaps because ofdrought,orashortageofnaturalresources.TheFremontdidn’thaveawrittenlanguage, soarchaeologistshavehadtoguesswhat their lifeandculturewaslike.Someofthebestcluesarethemanyimagescarvedandpaintedontothesurfacesofrock,calledpetroglyphsandpictographs.ManyarestillvisibletovisitorsthroughoutDinosaur.

PETROGLYPHCOMESFROMTWOWORDS,PETRO,WHICHMEANSROCK,ANDGLYPH,WHICHMEANSASYMBOL

THATCANBECARVEDORPAINTED.

TheFremontpeoplecarvedimagesofhumans,animals,andabstractsymbolslikecirclesandspirals,intothesandstoneatDinosaur.Wedon’tknowexactlywhatallof thesesymbolsmean,orwhytheFremontpeopleusedthem.Theycould represent clans, or have been used for hunting, ceremonies, or simplyartisticreasons.Whatdoyouthink?

IfyouvisitDinosaurNationalMonument,don’tevercarveinthenaturalrocksyourself.Don’t touch petroglyphs or pictographs that you see either becausethe natural oils from your hands can harm them. Also don’t try to take arubbing or tracing fromone; it’s too easy to damage them.Take pictures or

drawasketchinstead!Wewantthepetroglyphsandpictographstobearoundforgenerationsofpeopletosee.


MAKEYOUROWNFOSSIL

1Cutoffthetopofthemilkcartonsoit’sabout4inchestall.Spreadpetroleumjellyontheinsideofthecartonandtheobjectyou’remakingafossilof.

2Pourabout2cupsplasterand1cupwater intotheziplockbag.Sealthebagand squish the mixture until it is thick, but pourable and smooth. Pour theplasterintothecarton.

3Presstheobjectyouwanttomakeafossilofintotheplastersothatone-halfiscoveredbyplasterandrestisexposed.Letitstaythereuntiltheplasterstartstoset. Carefully remove the object and let the plaster continue to dry, about 30minutesormoredependingonhowhumid theday is.Younowhaveaplastercast.

4 Coat the cast and the inside of the cartonwith petroleum jelly.Mix 1 cupplasterofparis,½cupwater,andpaprikaorfoodcoloring.

5Pourtheplasterintoyourmold.Youcaneitherpouritinuntilitjustfillstheimpressionofeachobject,oryoucanpourinalloftheplastersothatit’saninchormorethick.Letitdrythoroughly,about2hoursorovernight.Thisisaplastmold.

6Carefully remove themold fromthecast.Youcanmakemoremolds ifyoulike.When you’re done, use fine sandpaper to smooth the surface, and paintyourmoldifyoulike.

What’sHappening?Youaremimickingawaythatrealfossilsaremade.Whenyoupresstheobjectintothewetplaster,itislikeabonebeingburiedinmud.Themudwouldhavehardened around the bone, just like the plaster hardened. Then, the bonedissolves over time, leaving a cast. Sometimes, that’s all that’s found. Butsediment can also fill that cast,making amoldof theoriginal bone.There areotherwaysthatfossilsform,suchasmineralsdirectlyreplacingthesofttissuesofbones.

Youcanalsomakecastsandmoldsofanimaltracksthatyoufind.Cutoffthebottomof themilkcarton,andpress themilkcarton (nowopenatbothends)intothesoilaroundthetrack.Pourtheplasterinandletitsetuplikeabove.

SUPPLIESemptyhalf-galloncardboardmilkcarton

scissors

petroleumjelly

3cupsplasterofparisfromthehardwareorcraftstore

water

largeziplockplasticbag

seashell,plasticegg,leaf,orotherdistinctiveshape

foodcoloringorpaprika

finesandpaper

Chapter6

PETRIFIEDFORESTNATIONALPARK

Ifyoulookaroundthehot,desert landscapeofArizonatoday, it’shardtoimaginethelandwasoncecoveredwithswamps,ferns,andforestsoftalltreesmuchlikepines.Butthat’sexactlywhatArizonawas like225millionyearsago, in theTriassicperiod.Theairwasextremelyhotandhumid,volcanoesspewedfireandashinthesky,andwater-lovingplantsandsmallanimalswereeverywhere.Largewater reptileshunted in the inland seas. Smalldinosaurshad justmadetheirappearanceonlandforthefirsttime.Whentreesweretoppledbystormsorfelloverwithage,theysometimesfellinto swamps and rivers. Volcanic ash and other sediments quickly coveredthem. Soaked by mineral-rich water, the ash and sediments kept the treesfromdecaying.NPSPhotosbyT.ScottWilliams

EVENTHOUGHIT’SILLEGALTOTAKEPETRIFIEDWOODFROMTHEPETRIFIEDFOREST,PEOPLETAKEMORETHAN

24,000POUNDSOFITFROMTHEPARKEVERYYEAR.SCIENTISTSWORRYTHATSOMEDAYTHEREWON’TBEAPETRIFIEDFORESTLEFTINPETRIFIEDFORESTNATIONAL

PARK.

WORDSTOKNOWsediment:looserockparticles.


inorganic:fromsomethingnotliving.

decay:torotordecompose.

earthquake:shakinganddisturbingoftheearth,oftenviolently,whichoccurswhentwoplatesontheearthslideunderandaboveeachother.

erode:towearawaybyweatherandwater.

petrifaction: the process in which thematerial in living cells is replaced bycrystals,turningtostoneovertime.

crystallize:toformintoarockwithacrystalshapeofflatsurfaces.

Whilethetreeswereburied,thelandchangeddrastically.Millionsofyearsofdinosaurscameandwent.Gradually,theswampsdriedupandthelandturnedtodesert.Earthquakesfoldedandtumbledthelandscape,creatingnewhillsand

valleys.Thelandwasuplifted,andwindandwatereroded layersofrockabovethe sediments that held the trees. Trees that had been buried under water instreams, thencovered inash, sand, andmud forhundredsofmillionsofyearswere exposed to the air again. But something happened to the trees all thoseyears ago when they were buried in sediments and soaked in ground water.Nature performed one of itsmost amazingmagic tricks: the trees had turnedfromwoodtostone.EntireforestsofpetrifiedtreeslayscatteredinpiecesacrossthedustyArizonahills,theirstonetrunksstreakedwithremarkablecolors:red,brown,black,blue,yellow,andevengreen.

PetrifiedForest:FromDiscoverytonationalmonumentFor thousandsof years communities ofNativeAmericans lived in and aroundthesestoneforests,usingstonefortradeandtoconstructsmallpueblos.

All that changed in 1851. The US Government sent Captain LorenzoSitgreavesonamissiontoseeiftheZuniandColoradoRiverscouldbeusedfortransportation.CaptainSitgreavesandhismenaccidentallywalkedup into thehillswhere they foundpetrified trees.CaptainSitgreaveswrote thatheandhismenfound,“massesofwhatappearedtohavebeenstumpsoftreespetrifiedintojasper, beautifully striped with bright shades of red, blue, white, and yellow.”Wordspreadquicklyabouttheamazingstonetrees.PeopletraveledtoArizonatotakealook—andsomesouvenirs—ofthewood.

FROMTREESTOSTONE

Petrifiedwoodwithapolishedsurface.

HowwerethetreesinthePetrifiedForestpreservedinthisway?Whydidthesetreesturntostonewhenbillionsofothersjustdisappearedintohistory?Becausetherewastheperfectmixofingredientsforpetrifcation:trees,water-soaked sediments, and volcanic ash. The water held lots of minerals:iron, cobalt, carbon, andmanganese. The volcanic ashwas full of amineralcalled silica. The silica combinedwith thewater and, over time, crystallizedwithinthecellsofthewoodandreplaceditwithquartz.Othermineralsinthewatergavethequartzcrystalstheiramazingcolors:

copper,cobalt,andchromium—green/blue

manganese—pink

silica—white,grey

carbonandmanganeseoxides—black

ironoxides—red,brown,yellow

NPSPhotobyT.ScottWilliams

WhentheTranscontinentalRailroadcamethroughthewesternstatesinthe1880s,moreandmorepeopleflockedtoremoteArizonatoseethefamoustrees,withmanyhopingtogetrichbysellingpetrifiedwood.Peopleworriedthatthe…naturalwonderwoulddisappearwithina fewyears’ time. In1906,after thepassage of the Antiquities Act, President Theodore Roosevelt named thePetrifiedForestthefourthnationalmonumentintheUnitedStates.

IN2005,SCIENTISTSFIGUREDOUTHOWTOMAKE“INSTANT”PETRIFIEDWOOD.THEYSOAKEDWOOD

CUBESINHYDROCHLORICACIDFORTWODAYS,THENINASILICASOLUTIONFORTWOMOREDAYS.THEYLETTHECUBESTHOROUGHLYAIRDRY,THENBAKEDTHEMINANOVENFILLEDWITHARGONGASATATEMPERATUREOF1,400DEGREESCELSIUSFORTWOHOURS.WHENTHEY

OPENEDTHEOVEN,THESCIENTISTSHADLITTLECUBESOFPETRIFIEDWOOD!MOTHERNATURE,OFCOURSE,

DIDN’TUSEAHIGHTEMPERATUREARGONOVEN,BUTASPECIALENVIRONMENTAND225MILLIONSYEARS.

WORDSTOKNOWhydrochloricacid:astrongacidthateatsawayatwhateverisinit.

solution:asoliddissolvedinaliquid.

argongas:anodorlessgas.

Transcontinental Railroad: a railroad built across the United States in the1860sthatfosteredthewestwardmovementofpeople.


PaintedDesertTheentire landscapesurrounding the fossilized trees isaworkofart.MuchoftheregioniscalledthePaintedDesert.Fromadistance,thePaintedDesertlookslike colorful, striped powder puffs, soft and flufly. It looks old, like it’s beenerodingforever.Notso!Thesoftlayersonlybeganerodingrecently,about6to15millionyearsago.

ThePaintedDesertlayersaremainlymudstonesandclaysthatformedwhenmudmixedwith volcanic ash and changed to bentonite, a clay. The beautifulreds, blues, and greens come from minerals contained in the rocks and theconditionspresentduring formation.Someof theclay iscappedbyrock that’sharderandresistserosion.Onceerosionbreaksthroughthatcapstone,though,theclaysunderneatherodeveryquickly.Whenitrains,theclayexpands—itcanabsorbseventimesitsvolumeinwater!Thenwhenitdries,thesurfacecrackssomuchthatit’scalled“elephantskin.”Thatmakesitextremelydifficultforplantsto take root, and with no plants, the clay erodes easily. Heavy rains in thesummerremoveasmuchasaquarter-inchofrockeachyear.Thatmaynotseemlike verymuch, but asmuch as 2 feet can erode in 100 years.Rain also formsgulliesintherocks,creatingthesoft,roundedshapes.

NPSPhoto

ISTHATADINOSAUR?ACROCODILE?Scientists have foundmany fossil teeth in Petrified ForestNational Park fromaround 215million years ago. Thiswas during the Late Triassic period,whendinosaurs first appeared. The teeth looked like those from Stegosaurus,Triceratops, andduck-billeddinosaurs.These are plant-eating dinosaurs calledornithischian dinosaurs, which were known to have lived much later. Soscientists thought all of these teeth from the Triassic Period belonged todinosaurs. Complete fossils of the ancestors of meat-eating dinosaurs likeTyrannosaurus Rex and other long-necked plant-eating dinosaurs have beenfound in the late Triassic, so scientists thought that all of the major types ofdinosaursbeganevolvingatthesametime.


In2004,thatthinkingwasblownapartatPetrifiedForest.That’swhenafossilof a complete skeleton ofRevueltosaurus was discovered. Turns out, the teeth

belonged to an ancestor of the crocodile, not a dinosaur at all.Now scientistsquestionwhetheranyof the teeth found fromtheTriassicPeriodare fromtheornithischiandinosaurs.

So where did the ancestors of Stegosaurus, Triceratops and duck-billeddinosaurs evolve, and when did they first appear? This is one of manyunanswered questions that keepspaleontologists peeking under rocks.Maybeit’saquestionyou’llhelpansweroneday!

WORDSTOKNOWornithischiandinosaurs:plant-eatingdinosaurswithbeaks.


petroglyph: a rock carvingmade by pecking on a rock surfacewith anotherrockorchisel.

TRYTHIS!Youcanmakeyourownpetroglyphthesamewayyoumadeafossilinthelast chapter.Cut the topoff anhalf-gallon cardboardmilk carton so it’sabout 4 inches tall. Spread petroleum jelly on the inside of the carton.Thenmix2 cupsofplasterwithpaprika anda cupofwater in a ziplockbag.Aftersealing thebagandsquishing themixtureuntil it is thickandsmooth,pourtheplasterintothecarton.Whiletheplasterisdrying,drawpictures ofwhat kind of petroglyph youwant tomake. You canmake asymbol,likeaspiral,oraperson,oranimal.Itworksbestifyouusesimpledesigns.Whentheplasterisdry—about1hour—carefullytakeitoutofthecarton.Usingthenail,carveyourdesignintotheplaster.

FOSSILSANDARTIFACTS

The Petrified Forest is home to some of the best examples ofancient fossils ever found, as well as a huge collection of earlyNativeAmericanartifacts.

The petrified trees in the Petrified Forest come from the Late TriassicEpoch, which happened about 230 to 200million years ago, just at thebeginning of the dinosaur era. The fossils here are one of the mostimportantcollectionsofTriassiceralifeintheworld.

ThePetrifiedForestandthePaintedDesertthatsurroundsitcontainsomeofthebestexamplesofpetroglyphs intheworld.Thewritingsmayhavecome from Native Americans called the Anasazi. One petroglyph isnicknamed“TheNewspaper,”becausethereissomuchancientwritingonit.

Chapter7

GRANDCANYONNATIONALPARK

StepintotheGrandCanyonandyoustepintothepast.Therocksofthe canyon tell an amazing story. It’s a story of continents built,mountains raised, shallow seas teeming with life, climateschanging,andmostofall,thetremendouspowerofwater.

HowtheGrandCanyonCametoBeTheGrandCanyon reallyhas two stories—how the rockswere formed, andhowthecanyonwascarved—thattogethercreateitsamazinglandscape.

Theoldest rocks in theGrandCanyonarealmost2billionyearsold,andyoucanfindthemdeepinthecanyonattheColoradoRiver.Whenyouthinkof something growing, youmight think of a plant, or a child growing. Butwhentheserocksformed,NorthAmericaitselfwasgrowing.Tectonicplateswerecollidingandformingnewvolcanicislands.TheseislandssmashedontotheNorthAmericancontinent,causingthecontinenttogrowsouthward.Left:NPSPhotobyMarkLellouch;Right:NPSPhotobyMichaelAnderson

Withallofthiscrazy,turbulentactivity,magmabubbleduptothesurface.Iteither exploded in volcanoes or slowly cooled, forming granite beneath thesurface.Rockswereburiedandheatedsomuchthattheystartedtobendandfoldlike silly putty, and actually changed into different kinds of rocks. This is aprocesscalleddynamicmetamorphism.Therewerealsorocksthatformedfromthe accumulation of sediments. These rocks were faulted and tilted as thecontinentrifted,orbrokeapart.TherocksatthebottomoftheGrandCanyonshowallofthesechangesandconditions.

Thereisalargegapintime,calledtheGreatUnconformity,wherethesefoldedand tilted rocks eroded. Since the land was much lower, shallow inland seasfilled the area,much like theMediterranean Sea today. The seas rose and fell,forming different layers of rock. Sandstones formed in beach environments,whilemudstones and limestones formed farther offshore. The layer of rocksthat were deposited haven’t been folded or deformed, forming a layer cakeappearance.During all of this time, complex lifewas evolving, and theGrandCanyonhas a rich storeof fossils.Thenabout65millionyears ago, the entireregionwaspusheduptoaboutamilehighinelevation.

WORDSTOKNOWColorado River: the river that carved the Grand Canyon and flows at itsbottom.

tectonicplates:huge,movinginterconnectedslabsoflithosphere.


volcano: a vent in the earth’s surface, throughwhichmagma, ash, and gaseserupt.


rift:whenthelithospheresplitsapart.

erode:thegradualwearingawayofrockbywater,glaciers,andwind.

TherocksthatweseeintheGrandCanyontookalongtimetoform—about1,600millionyears.Theriveritselftookfarlesstimetocutthecanyon—atmost55millionyears,possiblymuchless.Howdidthecanyongetsodeepandwide?

THEBOTTOMOFTHECANYONISABOUT25DEGREESWARMERTHANTHETOP,MAINLYBECAUSEOFTHEHUGE

CHANGEINELEVATION.

Itmight seem strange in such a dry area, but the canyon formed from theerosivepowerofwater.TheColoradoRivercarvedthechannelitselfandcarriesawaysediment. Ingeneral, thehigher inelevationariver is, themorepower ithas to carve a channel. Rivers that don’t drop much in elevation, like theMississippi,are“lazy”riversthatslowlywindbackandforthcarryingsedimentbut not carving deeper into the riverbed. But rivers that have a large drop inelevationmovefasterandcarvenarrow,deepchannels.TheGrandCanyonsitsveryhigh—thousandsoffeetabovesealevel—sotheColoradoRiverhasalotofenergytocarveitschannel.

Adifferentsourceofwatercausedthecanyontobewide:rain.IndryclimatessuchastheGrandCanyon’s,raincomesrarelybutinshort,violentstorms.Thereisn’tmuchvegetationorsoiltoabsorbtherain,soheavyraincausesflashfloods.Mostofthetime,thereisn’tmucherosionofthesidesofthecanyon.Butwhenthere is, the floods carry rocks and even large boulders down into the mainchannel.TheColoradoRiverthencarriesthoserocksandbouldersdownstreamandoutofthecanyon.

Geologists are trying to figure out the timing between a feature called theKaibabUplift anderosion fromthe river.TheKaibabUplifthasa slightdomeshape.Theproblem,ofcourse,isthatwaterdoesn’teverflowuphill.It’sforthesamereasonthatifyoujumpupyoualwayscomebackdown:gravity.

NPSPhotobyMarkLellouch

WORDSTOKNOWsandstone:asedimentaryrockcomposedofsand-sizemineralorrockgrains.

mudstone:asedimentaryrockmadeofclayormud.



elevation:ameasurementofheightabovesealevel.

Geologistsusedto thinkthat theColoradoflowedin itspresentcourse fromeasttowest,andtheareaintheKaibabUpliftwaspushedupatexactlythesamerateastheriverwascuttingdown.Slowandsteady.It’sabitlikecuttingalayercake by holding the knife steady above the cake, and lifting the cake up“through”theknife.

Most scientists don’t see such a simple picture anymore, though, becausethere’sevidencethattheupliftbeganmuchearlierthanmostpartsofthecanyonformed.Until fairlyrecently,mostscientistsagreedthat thecanyonwascarvedbytheColoradobeginningabout6millionyearsago,eventhoughtheydisagreedabout the details. But recent studies have questioned even that. Some data

indicatesthatsomepartsofthecanyonformed55millionyearsago.Otherdataindicatescarvingbegan17millionyearsago.Butacanyonthissizewouldhavealot of sediment that would be deposited at itsmouth, and there wasn’tmuchsedimentdepositeduntilabout6millionyearsago.Somanyscientistsstillthinkthat’swhencarvingbegan.

HOWSCIENTISTSWORK

Scientists use the scientific method in their work. An important step in thescientific method is making careful observations. Geologists frequently usethese observations to form a hypothesis, which is an explanation for whysomething happened, then testing that hypothesis. Sometimes a hypothesisneed to be revised if evidence indicates another explanation is better.Geologistscan’tgoback in time toperformexperiments.But theyconstantlycompare the evidence in the rock record with current processes today. So ageologistmightuse information abouthow rivers that are active today carvetheirchannelstofigureouthowtheColoradoRivercarvedtheGrandCanyon.

Scientistspresent theirevidenceandconclusions in scientific journals so thatotherscientistscanlookatthesameevidenceandseeiftheycanreproducetheresults. Scientists oftendisagree aboutwhat evidencemeans. Sometimes theypropose a different hypothesis forwhy something happened.Or, theymighthave more evidence that either agrees or disagrees with what others havefound. It’s like having a slow argument overmany years. Each new piece ofevidence adds to the picture. Eventually, there’s enough evidence that leadsnearlyallscientiststoagree.Sometimes,thatcantakemany,manyyears.Rightnow, there are many hypotheses about how and when the Grand Canyonformed,withlotsofresearchthatisprovidingnewevidence.Itwillprobablybemanyyearsbeforeeveryoneagrees.Butthepushandpulloffiguringouthowandwhysomethinghappenedispartofwhatmakesscienceinteresting.

NPSPhoto

The picture of how the canyon formed looks to bemore complicated thanpreviouslythought.Theremayhavebeenoneormoreearliercanyonsformedindifferent places and at different times, whichwere then linked together at theKaibabUplift to formtheGrandCanyonweknowtoday.Onething iscertain:geologistswillkeeplookingatrocksinordertofindtheanswers.

THEGREATUNCONFORMITYWhen sedimentary rocks are formed, the layers are horizontal, and the oldestrocks are on the bottom. Sometimes those layers are later tilted or folded.Sometimes time goes by when no rocks are formed, or the rocks that wereformedareerodedaway.Thismakesagap inagebetweenrock layers thatarenext to each other. The gap is called an unconformity. Think of it as pagesmissingfromabook.

Therearesmallunconformitiesinmostrocks,includingbetweenmanylayersofrockintheGrandCanyon.ButtheGrandCanyonalsohasahugegapcalledtheGreatUnconformity, and it’s among theworld’sbestknownandeasiest tosee. In places the Great Unconformity represents a gap in time of over onebillionyears!

THEGRANDCANYONAVERAGES10MILESACROSSFROMTHENORTHRIMTOTHESOUTHRIM,ISOVER1MILEDEEP

INPLACES,ANDISABOUT277MILESLONGALONGTHERIVER.

COLORFULSTAIRSTEPSTheGrandCanyonlooksabitlikeit’sasetofstairsbuiltforagiant.It’saseriesofsteep,nearlyverticalcliffs,alternatingwithmoregradualslopes.Thecliffsareformedfromrelativelyhardrocks like limestoneandsandstone.Theslopesareformed from softer rocks like shale that erode more easily. The rocks at thebottom of the canyon are crystalline and very hard, which is why the innercanyonissonarrow.Eachrocktypehasadifferentcolor—shadesofred,cream,brown,andgreen.Thesedifferentcolorscomefromverysmallamountsofironandotherelementsintherocks.

FIVELIFEZONESTheGrandCanyon contains five out of seven life zones and three out of fourdeserttypesfoundinNorthAmerica.Lifezonesareregionsofplantandanimalcommunitiesbasedonclimateandtemperature.BecausetheGrandCanyonhassuch a huge change in elevation in such a relatively small area, it also has atremendous variety of plants and animals. It’s like traveling from Mexico toCanada.Butonlyinthespaceofafewmiles.Thereareover2,000knownspeciesof plants, fungi, and lichen found in the park, and over 500 known species ofbirds,mammals,reptiles,andamphibians.

JOHNWESLEYPOWELL

In1869,theGrandCanyonwasuncharted.Asfarasweknow,noonehadfollowedtheColoradoRiverallthewaythroughthecanyon.JohnWesleyPowell and nine companions set out on a scientific expedition. He was anunlikely leader;hehad lost anarmdue towar injuries, andhehadnever ledsuchatripbefore.

Thegrouplosttwooftheirfourwoodenboatsandmuchoftheirsupplies,andnearly starved.Threepeoplewho left the trippartway throughwerekilledby

nativesorsettlersastheyclimbedoutofthecanyon.Halfstarved,membersofthe expedition couldn’t even stop to gathermuch scientific information. ButJohnWesley Powell andmost of his group survived, and he became a hero,known as “the conqueror of the Colorado.” He went on to organize moreexpeditionsandbeganthefascinatinggeological,biological,andculturalstudiesoftheGrandCanyonthatcontinueontoday.

GrandCanyonNationalParkMuseumCollection

MAKEYOUROWNMINI-CANYON

1Rollouttwocolorsofclayaboutaquarter-inchthick.Stackthelayersofclayontothecardboard.Thesearelikethelayersofrock.

2Withthelayersflatonthetable,pushfrombothsides.Iftheclaystickstothecardboard, lift themiddleup into at least one fold.Yourhands are like forcesfromtwocontinentspushingonrocks.Themiddleisafold.

3Holdingthewiretaut,useitlikeaknifetomakeacutthroughthetoppartofthe folded layers, parallel to the table. You should see the underneath layershowingthrough.Thisisliketheforcesoferosionlevelingoffasurface.

4Rollouttheothercolorsofclayaboutahalf-inchthick.Stackthemontopofthefoldedclay.

5Chooseadirectionforthe“river”torunthroughtheclay; itshouldbeatanangletohowyourhandswereplaced.Runyourfingernaillightlyacrossthetop

toshowwheretheriverwillrun.

6Oneithersideof the“river,”maketwoverticalcutsparallel to theriverandthroughthetoplayerofclayuntilyoureachthenextlayer.Peelawaytheslabofclaytorevealthenextlayerofclayunderneath.Thistoplayerisacliff-forminglayerofrock.

SUPPLIESatleastfivecolorsofplayclay

cardboardabout12inchessquare

rollingpin

thinwire

blueyarnorembroiderythread(optional)

7Onthenextlayer,maketwocutsatanangle;thisisaslopeforminglayerofrock.Placethewireatthebottomofthetoplayerandpullitdownandtowardstheriveruntilyoureachthenextlayer.Repeatontheothersideoftheriver,thenpeelawaythislayer.

8Continuecuttingawaylayers,alternatingcliffsandslopesuntilyoureachthelowest folded rocks.MakeaV-shapedcut through the folded layers, almost tothecardboard.Ifyou’dlike,cutapieceofblueyarnandplaceitatthebottomofthe“V”tobetheColoradoRiver.

THECOLORADORIVERSTRETCHES1,400MILESFROMTHEROCKYMOUNTAINSTOTHEGULFOFMEXICO,AND

DROPSOVER14,000FEET.

What’sHappening?ThisisasimplifiedmodeloftheGrandCanyon,withfarfewerlayersandnosidecanyons. The clay at the bottom represents the oldest rocks, formed almost 2billion years ago. Those rocks were folded and faulted due to tectonic platescolliding,and later, riftingof thecontinent. Inreality, the typesofrocks, folds,

andfaultsaremuchmorecomplicated.TheslicethatyoumadeisliketheGreatUnconformity,representingtheerosionofalargeamountofrockmaterial.Therocksformedlaterremainrelativelyflatbecausetheyhavenotbeendeformedbytectonicactivity.Andlastofall,theriverhascutdownwardthroughtherocks.

Chapter8

LASSENVOLGANICNATIONALPARK

CliffLake

CinderCone

OnMay29,1914,LassenPeakrumbled.Thenextdayitexploded.Lassen Volcanic National Park preserves an incredible array ofvolcanic formations, from cinder cones and young lava beds to

active sulfurous vents and mud pots. Lassen Peak is the highestpeak in Lassen Volcanic National Park, and it is also thesouthernmost mountain in the Cascade Mountains, which runalong the west coast of North America.—It’s no coincidence thatthis range is close to the Pacific Ocean or that it has activevolcanoes.Lassenhasafierypast,andlikelyafieryfuture.

MORETHAN50VOLCANOESHAVEERUPTEDINTHEUNITEDSTATESINTHEPAST200YEARS.

NPSPhotosbyRussellVirgilio

WHENLASSENNATIONALMONUMENTWASESTABLISHED,ITHADN’THADANERUPTIONINHUMANMEMORY.IT

WASESTABLISHEDTOPRESERVETHE“EXTINCTVOLCANICFEATURES.”WHATASURPRISEWHENIT

ERUPTEDSEVENYEARSLATER!

LassenPeakis thehighestpeakinLassenVolcanicNationalPark.It isalsothesouthernmostmountain in theCascadeMountains,which runs along thewestcoastofNorthAmerica.It’snocoincidencethatthisrangeisclosetothePacificOceanor that ithasactivevolcanoes.Lassenhasa fierypast, and likelya fieryfuture.

TYPESOFVOLCANOESTherearefourmaintypesofvolcanoesthancanform.LassenVolcanicNationalParkhasexamplesofallofthese.

Shieldvolcanoes:Shieldvolcanoeshaveabroadconeformedbylayersofrunny,darkbasalticlavathatcanflowagreatdistancebeforeitcools.Thesevolcanoesform quietly, when lava pushes through a fissure. They can reach huge sizes.Mauna Loa, in Hawaii, is a shield volcano that reaches 33,000 feet (10,058meters)fromseafloortopeak!

WORDSTOKNOWlava:magmathathasrisentothesurfaceoftheearth.

basalticlava:lavathat,whencooled,becomesbasalt,agrayishrock.

fissure:alongandnarrowcrackinthegroundthatcanbeverydeep.

caldera:alargecratercausedbytheviolentexplosionofavolcano.

NPSPhotobyRussellVirgilio

Compositecones:Thesevolcanoesarealsocalledstratovolcanoes.Theyhavea

classic volcanic cone shapewith alternating layers of runny lava flows like theshield volcanoes and more explosive volcanic deposits. They often eruptexplosively, sometimes blowing off their tops. They also produce pyroclasticflows, which are enormous volumes of extremely hot gases, ash, and rocksrushingdownthemountainside likeanavalanche. Ifenoughmaterialexplodesfromacompositevolcano,thetopcollapsesandformsacaldera,orhugebowl-shapeddepression.Mt.St.Helens,inWashington,isacompositevolcano.

IN1974,THEVISITOR’SCENTERWASMOVEDBECAUSEITWOULDBEINTHEPATHOFANAVALANCHEIFTHERE

WEREMOREERUPTIONSOREARTHQUAKES.

Cindercones:Thesearesmall,steep-sidedhillsthathaveaclassicvolcanicconeshape.Theyarebuiltbyanaccumulationofashandblobsoflavathatbreakintosmaller cinders.When they’re actually erupting, they look like a lava fountain.Lassenhasnumerous cinder cones.Themost recent cinder cone eruptionwas350yearsago.

WORDSTOKNOWmagma:partiallymeltedrockbelowthesurfaceoftheearth.

plate:huge,moving,interconnectedslabsoflithosphere.

crust:thethin,brittle,outerlayeroftheearth.

acid:achemicalcompound.

fumarole:aventthatemitshotgases.

Volcanicdome:Inavolcanicdome,thelavaoozesoutandistoothicktotravelfar,soitbuildsupintoadome.It’sabitliketoothpastewherethecapisleftoffand the toothpastedriesout.The super thickmagma squeezesup through theventandcoolswhen it reaches theair.Thatmightsoundslowandboring,butthepressurecanbuildupandmakethesevolcanoesexplosive.LassenPeakisoneofthelargestvolcanicdomesonEarth.

Volcanoes can also form in rift zones. Rift zones are where the plates thatmakeuptheouterlayerofEartharepulling(orrifting)apart.Thecrustcracks,andmagmapushes out.Rift zones oftenproduce flat, thick plateaus of cooled

lava.

HYDROTHERMAL

TerminalGeyser

Lassen has a well-developed hydrothermal system. Hydro meanswater,andthermalmeansheat,andthat’swhatLassenhas—VERYhotwater.Togetahydrothermalsystem,youneedthreethings:lotsofgroundwater,rockthat has pores so that thewater can seep down, and a heat source.Rain andmeltingsnowseepdeepintotheground.Thewaterisheatedbymagmaabout5to 6 miles (8 to 9½ kilometers) underground. Hydrothermal systems alsoabsorbacids,minerals,andgases,whichiswhythere’softenasmellofsulfur.Whenthewaterisheated,itrisestoaboutonemilebelowthesurfaceandformsapoolofboilingwater. Steam then rises through fractures to the surfaceandforms fumaroles and boiling, thumping, mudpots. Big Boiler, the largestfumarole in the park, has steam jetting up that is as hot as 322 degreesFahrenheit (161 degrees Celsius). It’s one of the hottest steam vents in theworld!

TRYTHIS!

Gettwocansofsoda.Openonecanandtakeafewsips.Poursomeofthesodaintoaglassandletitsitforafewhours,thentasteit.Canyoufeelthedifferenceinthefizz?Nowgooutside,shakethesecondcanofsoda,andopen it (point it away from you!). Soda has dissolved gas in it, just likelava.Whenthegashaslotsoftimetoescapefromthelavaasitrisestothesurface,it’s“flat”like‘thesodayouletsitout,andthelavapoursoutontothe surface without much fizz. Gas that doesn’t have as much time toescapeislikeyourfizzysoda.Butifthere’saLOTofgasthat’strappedinthe lava, suchashappenswhen the lava is very viscous, it’s like the sodathatyou’veshaken;whenthepressureiffinallyreleased,lookout!

EXPLODINGVOLCANO,ORADRIBBLINGONE?Volcanoes are formed from liquid rock, or magma, coming to the surface.Sometimes magma cools before it reaches the surface.When that happens, itforms rocks thathave largegrains that you can see, like granite.Butwhen themagma comes all theway to the surface before it cools, it’s called lava, and itcomesoutthroughavolcano.

Lavacanslowlybubbleoutoftheearthorbeviolentlyejected.Thedifferenceinhowithappensisreallybecauseoftwothings:

How viscous, or thick, the lava is. Liquids that are very viscous, like honey,

resist flow.Lessviscous liquids, likewater, floweasily.Thick lava canexplode.Howviscousthelavaisdependsonwhatit’smadeof.Lavathathaslotsofsilica,whichislightercolored,ismoreviscousandlikelytoexplode.Darkerlavaswithlesssilicaarelessviscousandmorelikelytoflowsmoothly.

Howmuch gas (mainlywater vapor) is still in the lavawhen it reaches thesurface.Lotsofdissolvedgascreatespressureinthelava,whichmakesitmoreexplosive,likeasodacanthat’sbeenshaken.Themoretimelavatakestoreachthe surface, the more time there is for gas to escape, and the lava is “flat.”Viscosityalsoaffectsthegascontent,becausegasismoreeasilytrappedinmoreviscouslava.

Formulaforanexplosivevolcano?Thicklavawithlotsofwatervapor.

“FRYINGPANS”ARESHALLOW,VIGOROUSLYBOILINGPOOLSOFCLEARWATERFOUNDATLASSEN.

WORDSTOKNOWviscous:howeasilyasubstanceflows.Honeyisveryviscous;waterisnot.

silica:achemicalfoundinsandandquartz.


lahars:hugemudflowsthatformfromlavaandashmixingwithmeltedsnowandrain.Theycantravelupto40milesperhour,andwipeouteverythingintheirpath.

pyroclastic flows: high-speed avalanchesofhot ash, rock fragments, andgasthattravelonacushionofcompressedairupto150milesperhourandbeashotas1,500degreesFahrenheit.


FEATURESOFLASSENLassenispartoftheCascadeMountainRange,whichrunsfromnorthtosouthalong the Pacific coastline. The Cascades are part of the “Ring of Fire” thatencirclesthePacificOcean.Thesevolcanoeshaveformedbecauseoceaniccrustin thePacific is being subducted, or pushedunder continental crust inNorthAmerica.As the oceanic crust is pulled down into the earth, itmelts, and themagmarisesandpushesthroughthecontinentalcrustasvolcanoes.Continentalcrust has lots of silica, which makes the magma more viscous—and moreexplosive.

Lassenisalsoinfluencedbythestretchingoftheearth’scrusttotheeast.ThiscombinationofforcesactingintheregionhasproducedthearrayofvolcanoesinLassen.

HOWITALLHAPPENEDSomewherearound600,000to470,000yearsago,anancientvolcanoformedinLassen, called Tehama. After that volcano went extinct, other lava domesformed,followedbycindercones,shieldvolcanoes,andmorelavadomes.Then,about27,000yearsago,LassenPeakformedontheflanksoftheextinctTehamavolcano.Itprobablyformedinafewyearstime,thenlaydormantuntil1914.

COLUMNSOFASHANDSTEAMCANRISEMORETHAN12MILESABOVEAVOLCANOINLESSTHAN30MINUTES.THE

COLUMNSCANEXTENDFORHUNDREDSOFMILES,DROPPINGASHOVERHUGEAREAS.WHENKRAKATOAERUPTEDIN1883,ASHROSETO50MILES,ANDITWAS

HEARD2,200MILESAWAY.WHENYELLOWSTONEERUPTED2.1MILLIONYEARSAGO,ITPRODUCEDENOUGHASHTOCOVERTHEWESTERNHALFOFTHEUNITEDSTATESIN

FOURFEETOFASH.


When Lassen erupted in 1914, if you were a fly in the air (and in thevolcano),thisiswhatyoumighthaveseen:

May29,1914:Everything’squiet,atleastonthesurface.Hasbeenforthelast27,000years.

May30,1914:Asteamexplosion!Magmahasbeenrisingtowardthesurface,and heating the underground water. The hot water turns to steam andexplodesoutofthevolcanounderpressure.

May 1915:Over 180 steam explosions have erupted fromLassen in the pastyear,andthere’sacrater1,000feet(305meters)across.

May14,1915:Glowingblocksof lavabouncedownLassen,andadeepredglowisvisible20miles(32kilometers)away.Thenextmorning,thecraterisfilledwithlava.

May19-20:Thelavaspillsoutofthecrater,meltingsnowinanavalanche.Alahar,ormudlfow,racesdownthesideofLassen.Meltedsnow,hotlava,mud,rocks,trees:it’sadevastatingmudflowthatwashesoutHatCreeknearby,and

destroyshomes,bridges,andbuildings.Peopleareawakenedbytheroarofthemudflowandgetoutjustintime.

May 22, 1915: B.F. Loomis, an amateur photographer, hikes down withfriends to take pictures of the area, called the Devastated Area. Lucky forthem,theyrunoutoffilmandhavetogoback,because…

May22,1915,afewhourslater:Thebiggestexplosionyet!Ahugepyroclasticflowchargesdownthevolcanoat60miles(96kilometers)perhour,withgases,rock,andbitsoflava.Meltingsnowturnstheflowintoalaharthatrushes10miles (16 kilometers) down and floodsHatCreek valley again.Volcanic ashrisestomorethan5miles(9kilometers)abovethepeak,andrainsdownashupto310miles(500kilometers)away.

1917: Smaller explosions continue, but things are quieting down as Lassenbeginsanotherperiodofdormancy,until…whoknowswhen?

MAKEYOUROWNFOAMYVOLCANO

SUPPLIES

wide-mouth,shortplasticbottle,suchasjuiceorsportsdrink

water

stiffpaperorfunnel

tablespoon

bakingsoda

dishsoap

foodcoloring

trayorbakingpan

modelingclay

vinegar

1Fillthebottlehalffullofwarmwater.Usethefunneltoaddthreetablespoonsofbakingsoda.

2Addasquirtofdishsoap.Holdyourhandoverthetopandshakethebottletogetitfoamy.

3Addseveraldropsofredfoodcoloringandtwodropsofyellowfoodcoloring,oranyothercoloryou’dlike.

4Setthebottleonthetray.Quicklyshapethemodelingclayaroundthebottleintoa cone.Adjust the cone tomake it levelwith theopeningofbottle.Don’tblocktheopeningofthebottle.

5Usethefunneltoquicklypourinvinegartojustbelowtherim.Removethefunnelandwatchyourvolcanoerupt!

Chapter9

CRATERSOFTHEMOONNATIONALMONUMENT

NorthCraterFlowTrail

Monoliths

CratersoftheMoonNationalMonumentandPreserveisastrangeplace. President Calvin Coolidge called it “a weird and scenic

landscape peculiar to itself,” when he established it as a nationalmonument in1924.Steppingonitsstrange,dark lavashapes,youcould imagine thatyou’reon themoon itself, rather thanhereonEarth—hencethename.Therearemanyadjectivesyoucouldusetodescribe its unique landscape: unearthly, beautiful, fascinating,cool. And, of course, strange—amazingly, terrifically, andwonderfullystrange!

YOUCANSEETHELAVAFLOWSINCRATERSOFTHEMOONFROMOUTERSPACE!

NPSPhotos

WORDSTOKNOWcrater:abowl-shapeddepression,usuallyinthetopofavolcaniccone.

lava:magmathathasrisentothesurfaceoftheearth.

volcano: a vent in the earth’s surface, throughwhichmagma, ash, and gaseserupt.

riftzone:anareawheretheearth’scrustispullingapart.


fissure:acrackinthesurfaceoftheearth,fromwhichmagmacanerupt.

basalt:a typeofrockthat formsfrommagmadeepintheearthflowingonto

theearth’ssurface.

SLOWDOWN:RIFTZONEAHEADCratersoftheMoonispartofahugearea,calledtheSnakeRiverPlain, that iscovered with volcanic deposits. It contains the Great Rift volcanic rift zone,where the earth’s crust is rifting, or pulling apart. The Great Rift varies fromabout1to5miles(1½to8kilometers)inwidth,andmostofitiscontainedinCraters of the Moon National Monument. Rifting is always happeningsomewhereonEarth,andit’shappeningnowatCratersoftheMoon.Mostofthetime it’s too slow to see—the crust is only pulling apart a few centimeters peryear,atmost.

Asriftinghappens,thecrustgetsthinner,dropsdown,andcracksform.Themagmabeneaththeearth’ssurfaceishot.Itrisesandpushesthroughthecracks.At first, themagmahasa lotofgas thatexpandsas it reaches the surface.Themagmaeruptsinalongcrack,orfissure—uptoamilelong—calleda“curtainoffire.” As some parts of the crack become clogged, the pressure forces theremainingmoltenlavaintofountainsthatcanshootover1,000feet(305meters)intotheair.Moltenblobsof lavaareexpelled,calledbombs.Then,asthegasesdecrease,thelavaflowsoutinhuge,runnyflowsthatcangoonfordays,weeks,oryears.

BEFORE:HOGLAVANOW:WAYCOOL!CratersoftheMoonhasallofthetypesofvolcanicfeaturesformedfrombasalticeruptions.Volcaniceruptionsofbasaltaren’tasviolentasother types,becausebasaltisrunnieranddoesn’tbuildupasmuchpressureasothertypesofmagmaoftendo.Butitmakesforsomeverycoolformations!Like…

Lavatubesyoucanwalkthrough:oneis800feet long!Another,theBearTrap Lava Tube, isn’t continuous, but it can be traced for over 10miles.Lavatubesformwhentheouterpartofalavaflowcoolsandhardens,whilethe inner part is still semi-liquid and flows out, leaving behind an emptytube.

BigCinderButte: at over 700 feet, it is one of the largest purely basalticcinderconesintheworld.

Lavabombs:globsoflavaspewedintotheair.

Treemolds: impressions of treesmade in the solidified lava. As the lavaenveloped a tree, itwould burn and releasewater that quickly cooled thesurroundinglava,leavingtheimpression.

Pahoehoelava:lavathathasaropy,smooth,orpillowysurface.ThewordisHawaiianmeaning “ropy.”Mostof the lava flows inCratersof theMoonarepahoehoe.

A’alava:atypeoflavaflowthathasasharpspinysurface.Itiscoolerandthicker than pahoehoe and breaks up as it flows. The word is Hawaiianmeaning“hardonthefeet.”

Blue andGreenDragon flows: bluish and greenish pahoehoe lava flows.Thecolorcomesfromablueglassontheoutersurfaceoftherock.

Opencracks:canbeseveralhundredfeetdeepandayard(meter)ormoreinwidth.

BASALTISTHEMAINTYPEOFLAVAFOUNDATCRATERSOFTHEMOON.

BigCinderButte

PahoehoeLavaToes

A’aLava

BlueDragonFlows

MAKEYOUROWNCHOCOLATERIFTZONE

SUPPLIES

1cupchocolatechips

saucepan

stove

shallowbakingpan

grahamcrackers

1Putthechocolateinthesaucepan.Meltoverlowheat.

2Pourthechocolateintothebakingpan.

3 Set two grahamcrackersnext to eachother on topof the chocolate. Slowlypushthemapartandslightlydown.

What’sHappening?Thegrahamcrackersrepresentthecrust,andthechocolaterepresentsthemeltedmagmafromthemantleunderneath.JustlikeatCratersoftheMooninthepast,whenthecrustispulledapart,themagmaispushedupthroughthecracks.

Chapter10

DEVILSTOWERNATIONALMONUMENT

DevilsTower

BelleFourcheRiver

Devils Tower is a rocky formation 1,267 feet tall (386 meters),rising from the Plains ofWyoming like a giant tree stump.Howcould such a landform come to be? Is it a pack of pencils left by

giants? For thousands of years people have told stories about theTower’sorigins.Eventoday,scientistsdon’tagreeonexactlywhathappened.TakealookatDevilsToweranditsgroovedsurface.Canyou thinkof an interesting story abouthow theTower formedorwhyitlookslikeitdoes?

OTHERNAMESFORDEVILSTOWERINCLUDE:BEAR’SLODGE,TREEROCK,BEAR’SHOUSE,ANDALOFTONA

ROCK.

WORDSTOKNOWsediment:looserockparticles.

sedimentary rock: rocks formed from the compressionof sand,mud, ashorotherrockfragments.

plates:huge,moving,interconnectedslabsoftheearth’souterlayer.


HOWDIDTHETOWERFORM?Back when dinosaurs roamed the earth, the area around Devils Tower wascoveredbyashallowsea.Sedimentsweredepositedovermillionsofyears thateventuallyturnedintolayersofrockcalledsedimentaryrock,suchassandstoneand mudstone. Movement of the earth’s plates then lifted the area up, andmagmarosetowardsthesurface.About49millionyearsago,themagmacooledtobecomeDevilsTower, forming thevertical columnsas it cooled. Itwas still

surroundedbythesedimentaryrocksthough.

DEVILSTOWERNATIONALMONUMENTWASTHEFIRSTNATIONALMONUMENT.

Rocks that form frommagma cooling are called igneous rocks, and they’refairlyhardbecausethegrainsofmineralsinthemareinterlocked.Sedimentaryrocksbreakmoreeasilybecausethegrainsaren’tboundastightlytogether.Morerecently—probablywithinthelast3millionyears—thesoftersedimentaryrockssurrounding Devils Tower eroded away, leaving the harder igneous rock ofDevilsTowertostandalone.

Geologists agree on all of that.What they don’t agree about iswhether themagma came all the way to the surface before cooling, or whether it cooledbeforeitreachedthesurface.SomegeologiststhinkDevilsTowerformedwhenmagma came to the surface and formed a volcano. They think the Tower iswhat’s left of the cone of a volcano. The evidence for that is the shape of theTower,especiallythewaytheverticalcolumnsflareoutatthebase,whichislikevolcanicnecks found elsewhere in theworld. It’s easy to pictureDevilsTowerbeingtheinsideofavolcanocone.

Mostgeologistsdisagreewiththistheory,though.Theythinkthatthemagmacooledbelowthesurfaceoftheearth.Why?

Becausetherearen’tanyothervolcanicrockssuchasashorlavaflowsinthearea. If there had been an explosive volcano, they would expect to see someevidenceofthat.Also,thesizeofsomeofthegrainsintheDevilsTowerrockislarger than isusually foundinvolcanicrocks.Largergrainsusually formwhencoolingisslower.Thisisbecausethegrainshavemoretimetogrowbeforethemoltenrockturnscompletelysolid.Magmatakeslongertocoolwhenitdoesn’treach the surface of the earth. Volcanic rocks cool quickly at the surface andusuallyhavefinegrains.

GeologistswillneedmoreevidencetofinallydecidewhetherthemagmathatformedDevils Tower cooled above or below the earth’s surface.What do youthink?

WORDSTOKNOWigneous rock: rock that forms frommagma cooling and solidifying. Igneous

rocks can form either beneath the surface of the earth or on the surface asvolcanicrocks.


erode:towearbyweatherorwater.

geologist:ascientistwhostudiesrocksandminerals.

volcano: a vent in the earth’s crust, through which magma, ash, and gaseserupt.

CLIMBINGTHETOWER

About4,000peoplecomefromallovertheworldtoclimbDevilsTower each year, using different “routes” up theTower. Climberstodaymostlyusetheirownstrengthtoclimbbywedginginthenaturalcracks.Theequipmenttheyuseisremovableanddoesn’tdamagetherock.Thelongestcontinuouscrackis400feet(122meters)long.

Native Americans have long regarded the Tower as a sacred site. Manyceremoniesoccur in June, and theNationalParkServiceasksclimbersnot toclimb during this month. In addition, some climbing routes are closed atdifferenttimesoftheyeartoprotectthenestsofprairiefalcons.

WORDSTOKNOWhexagonal:ashapethathassixsides.

joint:alargefracture,orcrackinarock.

radiometricdating: amethodofdetermining theageof rocksbycomparingthe amount of radioactive elements with the amount of the elements theybecomeaftertheydecay.

element:asubstancethatismadeupofatomsthatareallthesame.

radioactive decay: the process where certain elements lose particles andbecomeadifferentelement.

atom: the smallest particle of matter that cannot be broken down withoutchangingtheparticle’sproperties.Everythingontheearth ismadeofvariouscombinationsofatoms.

rate:speedofsomething.

BEARCLAWSORCOOUNGMAGMA?Devils Tower is striking because of its huge, hexagonal rock columns. OneNative American legend tells of two boys who had wandered far from theirvillage.Mato,ahuge,hungrybearwithclawsasbigasteepeepoles,chasedthem.TheCreatorheardtheboys’prayersforhelp,andraisedthegroundtohelpthemescape.Matotriedtoeatthem,butcouldn’treachthem,leavingscratchmarksallaroundtheTower.AfterMatoleft,aneaglehelpedtheboysofftheTower.

Geologists have another explanation.Whenmagma cools, the rock that formstakesup less space than themagma.Thiscreatescracksas themagmashrinks,like the cracks in dried mud. Geologists call these cracks rock joints. Whenmagma cools near or above the surface of the earth, those joints formverticalcolumns. The columns usually have five or six sides for the same reasonhoneycombshavesix-sidedcells.Itisthemostefficientwaytodivideasurface.

BothoftheseexplanationsfortheverticalgroovesatDevilsTowerarerealindifferentways—theybothtellussomethingabouttheTower.

OVER20NATIVEAMERICANTRIBESHAVEACULTURALCONNECTIONWITHTHETOWER.6INDIANNATIONSHAVELIVEDINTHEAREAATSOMETIMEINTHEPAST,INCLUDINGTHEARAPAHO,CHEYENNE,CROW,KIOWA,

LAKOTA,ANDSHOSHONE.THELAKOTAPEOPLECONSIDERTHETOWERTHEBIRTHPLACEOFWISDOM.

TRYTHIS!MAKECOLUMNSYou canmake your own columnswith cornstarch andwarmwater. You’llneedabrightlightwithabulbof100watts,onetablespoonofbleach,andaclear dish—a glass pie pan works well. Mix equal parts of cornstarch andwaterinthepiepanuntilthemixtureisaboutonetotwoinchesdeep.Getanadulttoaddthetablespoonofbleach.Stirwellandsetthepanseveralinchesunderabright lightforaboutaweek.It’sokayif the light isn’tonallof thetime,but itmight take longer todry.You’ll know it’s completelydrywhenyou see the following: the surface is drywhen you touch it; there are largedeep cracks in the cornstarch; the cornstarch has separated a bit from thesides of the pan; there’s a network of cracks when you look through thebottom.When it’s dry, put a cutting board on top of the pan and flip theboardandpanoversothatthecornstarchcomesoutontotheboard.Doyou

seeanyshapes?Gentlyprythecornstarchapartwithabutterknife.Didthecornstarchformcolumns?Dotheyhaveaparticularshape?

What’s happening? As lava cools, it shrinks. As soon as a crack forms, acombination of water and steam removes heat. The cracks start out in arandom pattern, but as they continue to form, the crack pattern becomeshexagonal because hexagons are more stable. Researchers have usedcornstarch inexperimentsnot toodifferent fromyours to learnmoreabouthowandwhylavacoolsthisway.

HOWOLDISTHATROCK?Geologistshavedifferentwaystofigureouttheageofrocks—thatis,howlongagoarockformed.Somemethodsworkbestforshortertimeperiods, like hundreds or thousands of years, and others for very long timeperiods like millions or billions of years. Radiometric dating is used forigneousrocks,liketherocksthatmakeupDevilsTower.

Whenmagmacoolstoformigneousrocks,therockshavevariousamountsofchemical elements. Some of the elements are radioactive and decay, whichmeans that theatoms loseparticlesandbecomeanewelement.Eachkindofradioactiveelementhasaknownrateatwhichitchangestoanewelement.Forexample,scientistsknowthatafter1.25billionyears,onehalfofthepotassiumin a rock will decay and become argon. They can then measure how muchpotassium is in a rock sample and compare it to the amount of argon, andcalculate theageof the rock.Geologistsused this typeofdating to show thatmagmacooledtoformDevilsTowerabout49millionyearsago.

MAKEYOUROWNIGNEOUSROCKS

SUPPLIES

cookiesheetthathassides

cookingspray

freezer

cottonstring

2buttons

2pencils

2glassjars

water

saucepan

sugar,about4cups

stove

potholder

Caution:Thisprojectinvolvesveryhotliquids,sogetanadulttohelp.

1Greasethecookiesheetwithcookingsprayandplaceitinthefreezer.Tieoneendof the string to abuttonandwrap theother endaroundapencil.Put thepencil over one of the glass jars so that the string hangs down into the glass.Adjustthelengthofstringsothatthebuttonisjustabovethebottomoftheglass.Dothesamethingwiththesecondjar.

2Pourabout1½cupsofwaterintoasaucepanandaddabout3cupsofsugar.Makesureyouhaveanadultforthispart.Heatthesugarwatermixtureuntilitboils,stirringuntilthesugardissolvesorthesyruphassmallbubblesinit.Cookthesugarsyrupovermediumheatfor3minuteswithoutstirring.

3 Remove the saucepan from the heat and let cool for 2minutes.With youradulthelper,carefullypourthesyrupintoeachjartojustbelowthebrim.Ifthereis extra sugar on the bottom of the saucepan, do not let it flow into the jars.Usingapotholder,movethejarstoawarmplacewheretheycanbeeasilyseen,butwillnotbedisturbed.

4 Put the remaining cup of sugar in the saucepan.Heat the sugar on low tomediumuntilthesugarturnsbrownandmelts.Bepatient—itwilltakeabout10minutes.Assoonasthesugarmeltscompletely,getanadulttohelpyoupouritintothecookiesheet.Beverycareful—thesugarisveryhot.

5Placethecookiesheet intherefrigeratororfreezeruntil thesugarsyruphashardened,about10minutes.Prythesugarglassoutofthecookiesheetandlookatitcarefully.Doyouseeanycrystals?

6 Set aside your sugar glasswhile youwait for crystals to growon the cottonstring in the jars.Bepatient!Aftera fewdays, takeoutoneof the stringswithsmallsugarcrystals.Waitforatleastaweekbeforetakingthesecondstringout.Thelongeryouwait,thebiggerthesugarcrystalwillgrow.Ifnocrystalforms,orifthewholeglassofsyrupturnsintoasolidlump,youmayhavestirreditwhileitwasboiling.Tryagain!

7 Compare your three examples of sugar. How do you think they mightcomparetohotmagmacooling?

What’sHappening?Whenyoucooledthehotsugarsyrupquicklyinthefreezer,itdidn’thavetimetoformanycrystals,butcameoutasakindofglass.Thesugarsyrupthatcooledinthejarshadalongertimeforcrystalstogrow.Thelongeryouleftthestringinthesyrup,thelargerthecrystalsgrew.

Igneousrocks,orrocksthatformfromthecoolingofmagma,forminasimilarway. When magma comes to the surface, it cools relatively quickly, and theminerals don’t have time to grow into larger crystals. Sometimes they cool soquicklythatvolcanicglass is formed,calledobsidian.This is likewhathappenswhenyouputthesugarsyrupinthefreezer.

Igneousrocksthatcomefrommagmacoolingundergroundhavealongertimetogrowbeforetheyharden,becauseit’shotterbelowthesurfaceoftheearth.Themineralshavetimetoformlargercrystals,usuallylargeenoughtosee.That’sonereasonwhygeologists think thatDevilsTower cooledbelow the surfaceof theearth—¿someofitsmineralsarecrystalslargeenoughtosee.

Chapter11

GREATSANDDUNESNATIONALPARK

SangredeCristoMountains

ChineseWalls

If you were hiking or snowshoeing at over 13,000 feet (3,963meters)throughthesnow-cappedridgesofthebeautifulSangredeCristo Mountains, about the last thing you might expect to seewouldbesanddunes.Sanddunes,afterall,occurwhereit’salwayshotandthere’snorain,likeintheMiddleEastorAfrica,right?Butifyoulookeddownintothevalleyfromyoursnowymountainpeakyou’d see the highest dunes inNorthAmerica.How in theworlddidsanddunesformhere?

IFYOUCOULDPILETHESANDFROMTHEDUNESINTOATOWERONEMETERSQUARE,ITWOULDREACHTOTHE

MOONANDBACKSIXTIMES!

Left:NPSPhoto;Middle:PhotoCourtesyofInteractiveEarth;Right:NPSPhoto

Togetdunes,youneedmorethanalotofsand:

Windstrongenoughtomovethesand.Togetverytalldunes,thewindalso

needstosometimesswitchtoblowingfromtheoppositedirectiontokeeppushingthesandbackonitself.

Thesandmustbeloose.Ifthesandishardenedbyminerals,orhasalotofvegetationanchoring it, itwon’t be shaped intodunes.Toomuch rainfallmakesthesandgrainssticktogetherandalsoallowsplantstogrow.

FOSSILSFROMTHEBOTTOMOFANANCIENTSEACANBEFOUNDINLAYERSOFROCKTHATARENOWHIGHINTHE

SANGREDECRISTOMOUNTAINS.

Likemanyplaces,thenaturalsettingatGreatSandDunesisbecauseofplatetectonics.About27millionyearsago,theearth’scrustbeganrifting,orpullingapart in this area.As the earth’s platespulled apart—generating abreak calledthe Rio Grande Rift Zone here—the crust broke into blocks. One end of theblockstilteddownward,formingthevalleythatcontainstheGreatSandDunes.TheotherendtiltedupwardtoformtheSangredeCristoMountains.Sediment,includingsand,washeddownfromthemountainsintothevalley.Thesedimentis2miles(3kilometers)deepinplaces.

WORDSTOKNOWsanddunes:aridgeofsandcreatedbythewind.


platetectonics:thetheorythatdescribeshowtheplatesmoveacrosstheearthandinteractwitheachother.

crust:thethin,brittle,outerlayeroftheearth.



GreatSandDunesandSangredeCristoMountainsNPSPhoto

WORDSTOKNOWdunefield:alargeareaofsandblownbywindintodunes.


adapt: when animals or plants change things about themselves over time inordertoblendinwithorsurviveintheirenvironment.


habitat:theenvironment.

alpine:landthatishigherinelevationthanwheretreescangrow(thetreeline).Alpinelandistoocoldandwindyfortalltrees.

THETALLESTOFTHEGREATSANDDUNESARENEARLY750FEETTALL,ANDARETHETALLESTSANDDUNESINNORTH

AMERICA.THEY’RETALLENOUGHTOSKIDOWN!

Themountainsaffecttheflowofwindinthevalley.Ifthewindalwaysblewinonedirection, theduneswouldn’tgrowvery tall.Here, thewindusuallyblowsfromthesouthwest,pushingthesandtowardthemountains.Butduringstorms,thewindsblowbacktowardthevalley,pushingthesandintohigherdunes.

Thedunesarealsotallbecauseofthelackofwater.Onlyabout7inchesofrainfallsinthevalleyeachyear.Thereisnovegetationinthedunefieldsbecausethewindspreventplantsfromtakingrootandgrowing.Lackofwaterhelpskeepthesanddryandloose.Butwaterhelpsinanotherway.Therearestreamsthatflowaround the edges of the dunes. Wind blows sand from the dunes into thestreams,thenthestreamscarrythesandbacktowherethewindcanblowitintothedunesagain.Sothestreamsactabitlikeaconveyorbelt,recyclingsand.

WANTTOPLAYLEAPFROG?Whenthewindisstrongenough,itliftsgrainsofsandafewincheshigh, thendrops them.When they land, they bump into other grains ofsandandcausethemtojumpandgetcarriedbythewind.Likeleapfrog.Thiswholeprocessiscalledsaltation,whichisafancywayofsayingthatsandjumpsandbumpsinthewind.

TYPESOFAUNES:WHAGASHAPECANTELLYOUTheshapesofsanddunescantellyouabouthowtheyformed.ExamplesofallofthesedunesmaybefoundatGreatSandDunes.

Barchan: a crescent-shaped dune with “horns” pointing in the samedirectionthattheprevailingwindisblowing.Theseformwhereplantscan’tgrow,thereislimitedsand,andwindblowsfromonemaindirection.

Transverse:a longlineofduneswheretheridgesareperpendiculartothewind.Theyoftenformfrombarchandunesconnecting.

Parabolic:acrescent-shapeddunewiththe“horns”or“arms”ofthedunepointing upwind. They formwhen a section of sand with plants on it isblownawayby strongwinds.Thearmsareheld inplacebyplants, as the“nose”ofthedunemovesforward.

Reversing:talldunesthatoccurwhenwindblowsfromonedirectionpartofthetime,thenswitchestotheoppositedirectionpartofthetime.Thesearethetallestdunesbecausetheydon’tmoveforwardinthedirectionofthewind.Theygrowontopofthemselves.

Star:theseduneshaveastarshapewithseveralarms.Theyareformedinacomplexwindpattern,wherewindscome fromdifferentdirections.Great

SandDuneshassomestardunesinthenortheastcornerofthedunefield.

ReversingDunes

StarDunesPhotosCourtesyofInteractiveEarth

ANISLANDINCOLORADO?

TigerBeetle

GreatSandDunesNationalParkandPreserve isbestknownforitsamazingsanddunes,butitalsocontainsanincrediblevarietyofecosystems,andanimalsadaptedtothem.GreatSandDunesisanisland. It’s surrounded by vegetation though not water. An animal that isperfectly adapted to the harsh conditions of the dunes may not do so welloutsidethedunes.TheGiantSandTreaderCamelCricket,whichhasspinesonitslegsthathelpitdiginthesandisanexample.Thedunesarehometoseveralspeciesthatarefoundnowhereelseonearth,liketheGreatSandDunesTigerBeetle.Thisbeetleadaptsinthefollowingways:

Itstraightensitslegstokeepitsbodyawayfromthehotsand.

Itmakesshallowburrowsduringthedaytoshadeitself.

Whenitneedsheat,itholdsitsbodyclosetothesand.

The park has many different habitats, or places where animals live. Theseinclude the alpine zone high in the mountains with long winters and deepsnow,forests,sandygrasslands,andthedunefield.Theseverydifferentzonesarehometoawidearrayofanimals.

migratingbirdssuchassandhillcranes,thatcanflyupto500milesin10hours

Americanwhitepelicansandgreathornedowls

bison,whicharethelargestlandanimalsinNorthAmericaandweighuptoaton

Pronghorns,relatedtoantelopes—whichcanrunupto60milesperhour

bobcatsandcoyotes

hummingbird moths, which use a long mouth part to eat, called aproboscis,thatmakesthemlooklikeahummingbird

jackrabbits

hornedlizards,whichpuffupandpokeouttheirspinesaroundpredatorstoscarethemoff,andareperfectlycamouflagedinthesand!

MAKEYOUROWNSANDDUNES

SUPPLIES

cardboardbox,atleast2feetlongandwide

scissors

50-poundbagofplaysand,availablefromthehardwarestore

afewrocksofvarioussizes,uptothesizeofabaseball

blowdryer

water

1Makeacardboardtraytoholdthesand:Selectthesideoftheboxthathasthelongest length andwidth. Set that side on the floor.Cut the cardboardbox sothatitisopenonthetopandhasa6-inch-highwall.

2Scoopsandintothecardboardtraysothesandisafewinchesdeep.

3Usingtheblowdryer,blowsandsothatitpilesupintoduneshapes.DOTHISOUTDOORS!Tryplacingdifferentsizerocksinthebox,andblowtowardstherocks.Canyoumakeareversingdunebychangingwinddirections?Abarchandune? Try placing small rocks to anchor the sand to make a parabolic dune.Whathappenswhenyousprinklewateronthesand?Tryblowingthesandintoasmalldune,thensprinklesomewaterdirectlyontheduneandblowdrysandontopofthat.Isiteasierorhardertomaketallerdunes?Whathappensifallofthesandiswet?

What’sHappening?Youhavethethreethingsnecessaryfordunes:sand,windthat’sstrong,steady,andthatsometimesreversesdirections,andconditionsthatkeepthesandloose.Varyingthesecomponentsmakesdifferentshapeddunes.

Chapter12

WHITESANDSNATIONALMONUMENT

White SandsNationalMonument is a gorgeous and unique land.White,shimmeringsandstretchesindunesacrossavastlandscape.ItisbrilliantlybrighthereinthiscornerofNewMexico.Thedunesconstantly move and there is a fascinating array of plants andanimalsthathaveadaptedtothehot,desertclimate.WhiteSandshasgorgeous,brightwhitedunesthatseemtostretchonforever.The sand ispowderyand soft,unlikeanyyouwould findat abeach.That’sbecause it’smadeofgypsum,amineral thatdissolves inwater, just like saltdoes.MostplacesonEarth,andcertainlyatanybeach,aretoowetforgypsumsandtostayaround.Sohowdidthesegypsumdunesformhere?

WHITESANDSNATIONALMONUMENTHASTHELARGESTGYPSUMDUNEFIELDINTHEWORLD.

PhotosCourtesyofEricaBreeRosenblum,Ph.D.

Thegypsumsandsoriginated ina large inland sea.Youprobablyknow thatseawater contains salt, but it also contains many other minerals, includinggypsum.Alongtimeago,thedryNewMexicodesertwascoveredbyashallowsea,andasthewaterevaporated,mineralslikegypsumandsaltwereleftbehind.Those gypsum deposits were later lifted up into mountains, and you can seethemasalightstripeinthemountainssurroundingthearea.Asrainfallsonthemountains, itdissolves thegypsumandcarries someof itdown the sides, intothevalleybelow.

WhiteSandsislocatedinabasin,whichislikeabowl.Waterflowsin,butitdoesn’tflowout.Inlatesummerwhentherainscome,rainflowsintothelowestpartof thebasinandformsaveryshallow lake.Everyyear the lakecompletelyevaporates, leavingbehindthedissolvedgypsum.Thatgypsumisbrokendownintosand-sizedbitsandblownintothedunes.

WORDSTOKNOWadapt:achangeinanorganismthatmakesitbettersuitedtoitsenvironment.

gypsum: amineral that is found in seawater, which can form large depositswhentheseaevaporates.

mineral:inorganicsubstancethatisfoundinthegroundandinrocks.Notananimalorplant.

evaporate:whenaliquidturnsintoavapororgas.

basin:anaturaldepressioninthesurfaceofthe land,oftenwitha lakeat thebottomofit.

THARSHEBLOWSPlantsandanimalsatWhiteSands facehigh temperaturesand littlewater.Butthe toughest conditions at White Sands are the high winds that blow hugeamountsofsand.Plantscan’tgetupandwalkawaywhenthesandstartstocoverthem. Even though plants don’t have lungs, they still “breathe” and needexposuretotheairandsun.

Most of the plants grow around the edges of the dunes. But some unusualplantsdowellwithinthedunes,usingacoupleofinterestingadaptations:

Thesoaptreeyuccagrowsfasterthanthesandcancoverit.It’sstemshootsupasmuchas12inchesinayear,pushingthegreenleavesabovethesand.

The skunkbush sumac and other plants not only try to outgrow theblowingsand,butalsousebranchingrootstoanchorthesandandslowitsmovement. This network of roots forms a hard mound, like a pedestal.Whenthesandmoveson,theplantcontinuestogrowonthepedestal.

ISEEYOU.CANYOUSEEME?

Most lizards are green or brown. They would stand out so starkly atWhiteSandsthattheywouldbeahawk’sdinnerbeforeonedaywasfinished.ThelizardsatWhiteSandsusedtobebrown,beforethesandsstartedblowinginaround7,000yearsago.Howdidtheybecomewhite?Skincolorinlizardsisdeterminedbygenes,whicharelittlepacketsofinformation.Genesdeterminealotabouthowananimallooksandbehaves—thecolorofskin,eyes,whethertogrowa tail,whatkindsof foodtoeat.Genesarecontained ineverycellof

every animal. When the code for a gene changes, it’s called a mutation.Animalshavevariationsintraitslikeskincolorduetomutations.

Mutationscanbegoodorbadforananimal,butfortheWhiteSandslizards,themutationsleadingtowhiteskinsavedthem.Whenthewhitesandsstartingblowingintothearea,therewereprobablysomelizardswithlighterskin,andsomewithdarkerskinduetonaturalvariationsingenes.Thelighter-skinnedlizardswouldhavelivedlongerthanthedarkerones,sinceitwouldbehardfora hawk or other predator to see them against the white sands. Because thelighter lizards would have lived longer, they would have had longer toreproduceandpassontheirgeneforlightercolortotheirchildren.Eventually,throughmany generations, the skin would have become light enough to beclosetothestarkwhiteofthesands.Otheranimalshavechangedtheircoloraswell. The Apache pocket mouse is also pure white, and insects, scorpions,toads,andmammalsthatliveinWhiteSandshavealightercoloringthantheirneighbors.

PhotoCourtesyofEricaBreeRosenblum,Ph.D.

MAKEYOUROWNEVAPORITE

SUPPLIES

smallmixingbowl

hottapwater

tablesalt

largeandsmallspoon

shallowbakingpan

1Pourabout1cupofhottapwaterintothebowl.Scoopsmallspoonfulsofsaltintothewater.Stirthemixturewiththelargespoonaftereachspoonfulisadded.Keepaddingsaltuntilitdoesn’tdissolveanymore.

2Pourthemixtureintothebakingpan.Setthepaninaplacewhereitwon’tbedisturbed,ideallynearawarmwindowsill.

3Check thepanafter a fewdays. Is there stillwater?Doyou see any crystalsforming?Keepcheckinguntilallofthewaterhasevaporated.Whatdoyouthinkwouldhappenifyouaddedwateragain?

What’sHappening?Whenyouaddedthesalttothewater,itlookedlikeitdisappeared,butitwasstillthere.Whenthewaterevaporates,orbecomesagas,thesaltisleftbehind.ThisisverysimilartowhathappenedwhenseawaterevaporatedfromtheWhiteSandsarea millions of years ago, leaving behind the large gypsum deposit thateventuallybecamethegypsumdunes.

WORDSTOKNOWgenes: information in the cells of living things that determine traits of anorganism,suchashaircolor.

mutation:achangeinagene.

evaporite: a mineral that has formed by the evaporation of water, leavingdissolvedmineralsbehind.Examplesaresalt,gypsum,andcalciumcarbonate.

Chapter13

DEATHVALLEYNATIONALPARK

TheRacetrackandGrandstand

ArtistsDrive

It’snothardtoimaginehowDeathValleygotitsname,especiallyifyou visit in the summer. Anyone not prepared for the extremelyhigh temperatures and lack of water wouldn’t last long in thislonelypartofsouthernCaliforniaandNevada.ButtherewardsofDeath Valley are many: fascinating landscapes, unusual animalsadapted to the difficult conditions, and the chance to experiencesomeofthegreatestextremesfoundanywhereonearth.

THEDIFFERENCEBETWEENTHEHIGHESTPOINTATTELESCOPEPEAKTOTHELOWESTPOINTATBADWATER

BASINIS11,311FEET(3,455METERS).ANDIT’SSTILLINCREASING!

MiddleandRight:NPSPhotos

IT’SHOT…On July 10, 1913, the thermometer climbed to 134 degrees Fahrenheit (57degreesCelsius).That’sthehottesttemperatureeverrecordedinNorthAmerica(and,until1922,intheworld).In2001,therewere154daysinarowthatwere100degreesFahrenheit(38degreesCelsius)orabove.Andthat’sjusttheair.Theground gets much hotter: on July 15, 1972, the ground reached 201 degreesFahrenheit(94degreesCelsius).That’shotenoughtofryanegg!

IT’SLOW…DeathValleycontainsthelowestpointintheWesternHemisphere:282feet(86meters)belowsealevelatBadwaterBasin.About500squaremilesofthevalleyisbelowsealevel.

IT’SDRY…DeathValley averages less than2 inches (5 centimeters) of rain each year (it’sbeenabithigherinthelast30years).ComparethattoMobile,Alabama,whichreceives on average 67 inches (170 centimeters) of rain per year. In 1929 and1953, there was no rain recorded at all in Death Valley! But the rate ofevaporation in thevalley isup to1 foot (30centimeters)peryear.Soanyrainthatdoesfallisquicklyevaporated.

WORDSTOKNOWWesternHemisphere:thehalfoftheearththatincludesallofNorthandSouthAmerica.

sealevel:theleveloftheocean.

evaporation:whenaliquidturnsintoavapororgas.

WHY?Death Valley is in what is called a “rain shadow.”When storms head inlandfrom the Pacific Ocean, they pass over mountains and lose most of theirmoisturebyrainingorsnowing.Bythetimethecloudsreachtheotherside,theydon’thavemuchmoistureleftinthem.Andifonemountainrangeisn’tenoughtosucktherainoutof theclouds, thereare threemorebetweentheoceanandDeathValley.

DeathValley gets very hot for a few reasons. Because it’s so dry, the valleydoesn’thavealotofvegetation.Therocksandbaresoilheatupmoreeasilyfromtheintensesunthanplantswould—it’sthedifferencebetweenwalkingacrossabigparkinglotonasunnydayandagrassymeadowonacloudyone.Also,lowerelevations are hotter than higher ones. The shape of the land affects thetemperaturetoo.Asairheatsupitrises.ButDeathValleyissurroundedbyhigh

mountainsthattrapthehotair.

WhydoesDeathValleyhavemountainsallaroundit?DeathValleyispartofamuch larger region called theBasin andRangeProvince. In this region of thesouthwesternUnited States and northwesternMexico, the land is broken intohuge blocks that have rotated from their horizontal positions. The parts thatrotateup form themountains, and theparts that dropdown form the valleys.Whichleadstoanotherquestion.WhydidtheBasinandRangeProvinceform?Whatcausedthelandtobreakintoblocksandtilt?

The outer layer of the earth, called the lithosphere, is divided into pieces,calledplates.Inthisregion,theseplatesarepullingapart,whichcausesthelandto crack along large faults into blocks. The stretching is still going on, andgeologists think that eventuallyNorthAmericawill be divided into twopieceswith a new ocean forming between them. But it won’t happen anytime soon,becausethelandisonlymovingaboutahalfinch(1centimeter)peryear.

WORDSTOKNOWrainshadow:anareaonthedownwindsideofamountainrange.Whenwindsand cloudspass overmountains it rains, leaving littlemoisture for the otherside.

lithosphere: the rigidouter layerof the earth that includes the crust and theuppermantle.


alluvialfans:hugeareasofsedimentthatformaprons,orfans,atthebaseofdesertmountains.

playa:adriedlakebed.

saltpan:aflatareaofgroundcoveredwithsaltandotherminerals.

GEOLOGICFEAGURESOFDEATHVALLEYAlluvial fans.Hugeareasofsediment formaprons,or fans,at thebaseofdesertmountains.Whenrainfallsindesertsthereisn’tmuchvegetationtoslowtherain.Flashfloodsdevelopthatcarrylotsofsedimenttothebaseofthemountain.

SandDunes.Dunesrisealmost700feetintheairandarehometorareandendangeredspeciesofplantsandanimals.

Devils Golf Course. A huge area of rock salt that has been eroded intojaggedspires.Howdiditgetitsname?Itwasacoursethat“onlythedevilcouldplaygolfon[it].”

RacetrackPlaya.Thisdriedlakebed,orplaya,hasmysteriouscurvedtracks,but they don’t look like any animal. How did they form? Probably fromrocksthatarepushedacrosstheplayaduringwinterwindstorms.

Caverns. The most famous is Devils Hole, which is over 500 feet (152meters)deep.That’s about asdeep as a skyscraperof 40 storieswouldbetall.Itscaveformationsarebeingusedtodeterminechangesintemperatureforthelast500,000years!

Volcanoes.Volcanoesintheparkhavebeenactiveasrecentlyas300yearsago,leavingbehindcraters,lavabeds,andcinders.

SaltPan.Themainvalley inDeathValley is a closedbasin, sowater thatcomes indoesn’tgoout.Mostvalleyshaveariverrunning through them.Thisvalleyhaswaterthatflowsinfromthesurroundingmountainsduringthunderstorms,butitcollectsinshallowlakescalledplayasandevaporates.As the rain runs down the mountainsides, it dissolves salt and otherminerals.Whenthewaterevaporatesfromtheplayas,though,thesaltandothermineralsare leftbehind.DeathValleyhasoneof theworld’s largestsaltpans,over200 squaremiles (320kilometers) across and thousandsoffeetthick.

SandDunes

DevilsGolfCourse

RacetrackPlaya

SALTPANSCANBEDANGEROUS-MUDHIDDENUNDERNEATHTHESALTLAYERCANTRAPANDENGULFVEHICLES.INWORLDWARII,THEBRITISHUSEDASALT

PANINEGYPTTODEFENDTHEMSELVES.ITWASABARRIERTHATENEMIESCOULDN’TCROSS.

WHENTHEGOINGGETSTOUGH,THETOUGHADAPTTemperaturesover120degreesFahrenheit(49degreesCelsius) inthesummer,

andbelowfreezinginthewinter.Searingsunwithfewclouds.Verylittlewater.It’satoughplaceandyet,thereareover1,000kindsofplantsand440kindsofanimals that live in the park. Fifty of them live nowhere else on earth. ThekangarooLrathasadaptedtotheharshenvironmentbyreclaimingmoistureintheairwithspecialnasalpassages,andgettingALLofitswaterfromthefooditeats.Iteliminatesverylittleurine.Thekangarooratevensealstheentrancesofitsburrowduringthedaytokeepinthecoolerair.Here’showotherplantsandanimalshaveadapted:

KangarooRat

Plants lose water through their leaves during a process calledevapotranspiration.Desertplantshavesmallleaves,sotheyloselesswater.Somehaveleaveswithawaxycoatingtopreventwaterloss.Cactushavelosttheirleavesentirely,andhavespinesinstead.

Plantsoftenhaveverydeeproots,whichgodown10timestheheightoftheplant.Otherplantshave roots that are very shallow, but extendout in alldirectionstocatchwhateverrainfallseepsdown.

Someplantsmaketheirownshadewithtinyhairsontheirleaves.

Animals stay out of the sun. During the day, most animals sleep inunderground burrows, where the sand is much cooler, and come out atnight.Theanimalsthatdocomeoutinthedaystayintheshade.

Manyotheranimalsgetthelittlewatertheyneedfromthefoodtheyeat.NPSPhoto

DEATHVALLEYWASLUSHANDSUBTROPICAL30MILLIONYEARSAGO.FOSSILSHEREINCLUDELEAFANDFISH

YEARSAGO.FOSSILSHEREINCLUDELEAFANDFISHIMPRINTS,PETRIFIEDWOOD,ANDMAMMALANDBIRD

TRACKS.

EXTREMELIVING

Pupfish

TheDevils Hole pupfish live in only one place on earth: DevilsHole inDeathValleyNational Park. Devils Hole is a narrow, water-filledcavernover500 feetdeep.Theyonlyreproduceonashallowrockshelfthat measures only 10 feet by 33 feet and sits on the edge of the cavernentrance.Iridescentblueandonly1inchlong,thesefishareamystery:howdidtheygethere?Howdotheysurvive?

No one knows for sure how pupfish got to Devils Hole. Over the last 100millionyears,varioustypesofpupfishmigratedfromtheAtlanticOcean.Theyswam up rivers and lakes, which have since dried up, into theDeathValleyarea.When they came, the climatewaswetter and cooler.Then, as the lakesdriedup,mostfishwentextinct,butsomeadaptedandsurvivedinsprings.Buthowdid theDevilsHolepupfishget fromtheclosest spring, less thanamileaway,toDevilsHole?It’sapuzzlethatscientistsaretryingtopiecetogether.

The Devils Hole pupfish face tough odds: the water is hot—93 degreesFahrenheit(33degreesCelsius)becauseitreachesdeepintotheearth.There’sbarely enoughoxygendissolved in thewater. Limited sunlightmeans there’slimited food. Flash floods sometimes dump sediment and rocks on the shelf

wheretheylayeggs.Earthquakesfromaroundtheworldsometimesshakethewater.Sincethey’recutofffromotherbodiesofwater,thefishcan’tmovetoabetterenvironment.

TheDevilsHolepupfishpopulationdeclinedinthe1960s,whenthewaterlevelbegandecreasingbecauseofnearbypumpingofgroundwater.In1976theU.S.SupremeCourt—inthefirstrulingofitskindintheU.S.—stoppedthegroundwater pumping and the fish population recovered. Since the 1990s theirnumbershavebeendecreasingagain,reachingalowof38adultsinApril2006.Thistime,nooneknowsforsurewhy.Scientistsareraisingsomefishinotherlocations, carefully cleaning their habitat when it’s clogged with rocks andsediments,andprovidingextrafood.ThenumberofDevilsHolepupfishadultshasrisento126inOctoberof2008,upfrom92inOctober2007.Thatmaynotsoundlikemuch,but ifyou’rea fish living inthedriestplace intheU.S.andscrabblingtosurvive,it’shuge.

U.S.FishandWildlifeService

Chapter14

DENALINATIONALPARKANDPRESERVE

Almost everything about Denali National Park is extreme. Themountainthatitisnamedfor,Denali(alsocalledMt.McKinley)isthehighestmountain inNorthAmerica.Youwill findbrutalcoldthere—temperaturesas lowas-40degreesFahrenheit(-40degreesCelsius),withvery longdays insummerandshortdays inwinter.Theparkishuge,containingmorelandthantheentirestateofNewHampshire.Ithasstunningwildlife,fromgrizzlybearstoherdsofcaribou.Mostofall,ithasincrediblebeauty.

DENALIHAS6GLACIERSTHATAREOVER25MILESLONG.THELONGEST,CALLEDKAHILTNAGLACIER,IS44MILES

LONG.

Right:NPSPhotobyKentMiller

WORDSTOKNOW

crevasse:alargecrackinaglacierorindeepsnow,fromafewfeettohundredsoffeetdeep.

altitudesickness:sicknessfromgainingaltitudetooquicklyorfromstayingathighaltitudesforalongtime.Itcausesafluidbuild-upinthelungsandcanbedeadly.



THEMOUNTAINAt20,320feethigh,Denalitowersovereverythingaroundit.Fromitsbasetoitspeak, it rises over 18,000 feet. That’s a greater vertical rise than Mt. Everest,whichstartsfromamuchhigherplateau.

Each year fromMay through July over a thousand people try to reach thesummitofDenali.Thebitter cold, snowstorms,highwinds, andaltitudemaketheclimbdifficult,andusuallyabouthalfoftheclimbersdon’treachthesummit.Climbers have to learn to build snow caves, rescue other climbers fromcrevasses,andrecognizesignsofaltitudesickness.

DenaliispartoftheAlaskaRange,achainofmountains400mileslong.That’sbeenaroundforhundredsofmillionsofyears.Denalibegan formingabout56millionyearsago,whenthePacificandNorthAmericanplatescollided.Atthe

same time, a large pool ofmagma rose close to the earth’s surface and slowlycooled into granite,which is hard and doesn’t erode very easily.As the platescontinuedtosmashintoeachother,thelandbuckledandrose.Denaliisneartheboundaryofthetwoplates,soitisstillbeingpushedhigher.

MountMcKinley

CLACIERSONTHEMOVEGlaciers are huge hunks of ice thatmove. They formwhen snow falls in thewinteranddoesn’tmeltinthesummer.Thesnowaccumulatesandcompressesthesnowcrystals,whichlocktogether.Glaciersthickenattheirupperend,whereit’scolderbecauseofthehigherelevation,andmeltatthelowerend.

Whentheicegrowsthickenough—usuallyabout60feet(18meters)thick—itbeginstomovefromtheforceofgravity.There’sathinlayerofmeltedwateratthebaseof a glacier thathelps it glide along theground—usually a few inches(centimeters)eachday.Buttheycansurgemorethan100feet(30meters)inoneday.Glaciersarepowerful,andwhentheymove,theytakerocks,trees,andevenlargebouldersalongwiththem.As theserocksgetdragged, theycarvegroovesandwiden valleys into a “U” shape. If you see deep scratches on a rock, thenglaciershaveprobablybeeninthearea.Whentherocksgettothepointwheretheglaciermelts,theyfallout,andtheserocksarecalledglacialtill.

WORDSTOKNOWglacier:abodyoficethatslowlymovesdownslopeduetogravity.

glacialtill:depositsofrocksmadeattheendofaglacier.

ArcticCircle: the imaginary line around the earth, representing thepoint inthefarnorthwhere,atcertaintimesofyear,thesunneversetsorneverrises.

Hugefractures,orcracks,inglaciersformbecausedifferentpartsofaglaciermoveatdifferent speeds,orbecauseaglacier travelsover rough terrain.Thesefracturesarecalledcrevasses,andtheycanbeseveral feetwideandquitedeep.Sometimes, a crevasse can be covered over by the previous year’s snow.Mountaineers can fall into these hidden crevasses,which iswhy it is standardpracticeforclimberstotravelonglaciersinsmallgroupsropedtogether.

THEYOUNGESTPERSONTOCLIMBMT.MCKINLEYISGALENJOHNSTON,WHOWAS11YEARSOLDWHENHE

REACHEDTHESUMMITONJUNE17,2001.

Moose

WHAT’SINANAME?

Denali National Park was first called Mt. McKinley National Park, afterGovernorWilliamMcKinley ofOhio, later president of theUnited States. Butthe Koyukuk people, who speak the Athabaskan Indian dialect, have alwayscalleditDenali,whichmeans“TheHighOne.”

ARCTICCIRCLEThenorthernreachofDenali is200miles(320kilometers)southof theArcticCircle. This Circlemarks the placewhere onDecember 21,called thewinter solstice, the sundoesn’t riseabove thehorizon.On June21,calledthesummersolstice,thesundoesn’tsinkcompletelybelowthehorizon.TheclosertotheNorthPoleyougo(ortheSouthPole),themoredaystherearewhereitistotallydarkorlight.FormostofDenali,theshortestdayisabout4hourslonginDecember,andthelongestisabout20hoursinJune.

THEBIGFIVEDenalihasanincrediblevarietyofwildlife—birds,mammals,fish,andevenonespeciesofamphibian.Mosquitoesandotherinsects,ofcourse,areveryhungryinthe summers.Denali is probably best known for its largestwildlife, andmanyvisitorswanttoseewhataresometimescalledthe“BigFive:”

Caribou: largemembersofthedeerfamilywholiveinherdsofhundreds,roamingacrossthetundrainmajesticmigrations.Thousandsofyearsago,nativepeopleinEuropeandAsiatamedcaribou,whicharecalledreindeer.

Moose: Imagine carrying something as big as your best friend on top ofyourhead.Denalimoosehaveantlersasheavyas80pounds(36kilograms)!Moose are the largest animals in the deer family, andDenali’smoose areamong the largest in theworld.They canweighup to 1,500pounds (680kilograms).

Dall sheep: The beautiful, white,Dall sheep scramble on steepmountaincliffs,wheretheykeepawayfromwolves,theirmainpredator.Becausetheydon’tshedtheirhorns,youcantellhowoldaDallsheepisbycountingtheringsonthem.

Wolves: Wolves travel in packs, with a male and female leader, calledalphas.Denali has between 12 and 18packs, a fewofwhich livenear the

parkroad. Ifyou’re lucky,youmightseewolveshuntingor travelingnearthe road. They’re very efficient hunters.Working together, they can evenbringdownamoose!

Grizzlybears.Bearsmaylookcuddly,butgrizzliesweigh450pounds(204kilograms)andarefierce.Ifyoustayawayfromthemanddon’tleavefoodout, theywon’t bother you.They eatmostly berries andother vegetation.Grizzliescanloseuptoonethirdoftheirweightduringwinterhibernation!Denalialsohasblackbears,whicharesmaller.

Caribou

DallSheep

Wolf

GrizzlyBearNPSPhotosbyKentMiller

MeetTrout!

Meet Trout. She arrived in thisworld in 2007, alongwith threeotherpuppies,andshe’snowpartoftheDenalisleddogteam.TheDenali sled dog teamwas founded in 1917 by the first Denali Park Ranger,HarryKartens.He used them to visit remote areas of the park, to help himprotecttheamazingwildlifeinDenalifrompoachers.Likeallsleddogs,Troutisperfectlybredtoliveinthisharshclimate,andbegantrainingforherwork

well before she turnedone year old.After learning commands fromhumansand running alongside the rest of the team, at about 8 months, she washarnessedbesideanexperiencedsleddog.Whatareherdayslike?

In the summer, she spends a lot of timemeetingvisitors.Three times aday,teamsofdogs showvisitorshow theywork,bypullingawheeled sledoveragraveltrack.Ifyouvisit,youcanseeTroutandherteammates—alongwiththenearly50,000otherpeoplewhoseethemeveryyear.Thedogsalsogoonwalkswithvolunteers,enjoyingthelongsummerdaylighthours.

In the winter, Trout and her teammates do their real work. Together, theDenali sled dog teams travel over 3,000 miles over ice and snow into theinteriorofDenali.InFebruaryandMarch,whenthedaysbegingettinglonger,thepatrolsstayoutforweeks.Thedogsandtheirmusherfacewhite-outs,ice,deepcold,wind,orangrymoose.Thedogsteamslovetobeoutworkinginthewinter, though.They often take researchers—whomight be studyingwolves,glaciers,soundmonitoring,andweatherstations—outintotheinteriorof thepark,ortheymightbringsuppliesandfirewoodtosomeoftheRangerStationslocated far from roads. Besides preventing poaching, rangers don’t allow theuse of snowmobiles in the park. Snowmobiles can disturb herds of caribou,hibernating animals, or visitors enjoying the beauty and solitude of Denaliduringthewintermonths.

TheDenalisleddogteamsaretheonlyonesthathelpprotectaNationalParkintheUnitedStates.Troutisaproudmember.Maybeyou’llmeetheroneday!

TRYTHIS!MAKECREVASSESGetaSnickerscandybarandholditsoyourthumbsareunderneathinthemiddle,andyourindexfingersareontopneartheends.Slowlypressdownon the ends. The caramel layer underneath should bend, because it’sgooier,whilethetopchocolateandnutlayershouldcrack,becausethey’remorebrittle.Also,thetoplayerhastostretchmore.Asimilarprocessisatworkinglaciers,formingcrevasses.Ofcourse,whenyou’redonewithyourexperiment,you’llhavetoproperlydisposeofthecandybar.

WORDSTOKNOW

poacher:apersonwhohuntsillegally.

musher:leaderofasleddogteam.

white-out:whensnowsquallsaresoheavyyoucanonlyseeafewfeetinfrontofyou.

auroraborealis: lights in thenight sky that occur because of the interactionbetweenradiationfromthesunandtheoxygenintheatmosphere.

LIGHTS,ACTION…AURORA!AsyougoclosertotheNorthPole,youaremorelikelytoseenorthernlights,orthe aurora borealis. (In the Southern Hemisphere it is called the auroraaustralis). The sky can glow or shimmerwith colored lights—green, red, evenblue.Sometimesthelightslooklikecurtains.Inthefarnorth,thecolorscanbequite bright, and may shimmer for hours. The northern lights are caused byparticles from the sun, called the solar wind, colliding with the earth’s upperatmosphere.As they are absorbedby the atmosphere, gases in the atmosphereemitdifferentcolors.Theparticlesaredrawntowardthemagneticpoles,whichiswhythelightsareusuallyonlyseenfartothenorthorsouth.

MAKEYOUROWN“GLACIER”

SUPPLIES

half-gallonpaperboardmilkcarton

snoworfinely9crushedice

sandandsmallpebbles

paperorplasticlunchbag

coinsorothersmall,heavyobjects

freezer

scissors

woodplank

hammer

nail

thickrubberband

1 Rinse themilk carton andopen the top so it has a square opening. Fill thecartonwithlayersofsnoworshavedice,sprinklingthesandandsmallpebblesinbetween the layers. Let the snow settle and addmore snowand sanduntil thecartonisfull.

2Fillthelunchbagwithabout2inchesofcoinsandplaceitontopofthesnow.Placethecartoninthefreezerwiththeopensideup.

3Checkthecartoneverydayorso.Ifthere’sroomatthetop,takeoutthebagaddmoresnowandsand/pebbles,andreplacethebag.

4 After about a week, take the carton out and cut the paperboard containeraway.Ifyouhavetroublereleasingthepaperboard,runitunderwarmwaterforaminute.Whatdoesthesnowlooklike?Doesitlookmorelikesnoworice?

5Hammerthenailintothemiddleofoneendofthewoodplank.Puttheendoftheplankwiththenailupafewinchestoformanincline.

6Placetheice/snowblockatthetopoftheincline.Looponeendoftherubber

bandaroundtheiceandtheotherendaroundthenail.

7 Check your glacier every hour or so.What has happened to the sand andpebbles?Dotheyformanypatterns?Aretheysorted?

WhatsHappening?Whensnow,whichismadeoficecrystals,isunderpressurelikefromtheweightofthecoins,thefeatherysnowcrystalsbreakdownandformnewonesassolidice.It’sthesamestuff—frozenwater—butinsteadoftinyicecrystalswithairinbetween, it’s a solidcrystal icenetwork.Youmaynothavehadenoughweightandtimeforthesnowtocompletelyrecrystallize,butinaglacier,theimmenseweightof thesnowontopcausesallof thesnowunderneath torecrystallizeassolid ice.The sandandpebbles falloutof the iceas itmelts,much like in realglaciers.Theserockdepositsarecalledglacialtill.

THESORTINGTRICK

1 Fill both jars almost to the top with sand. Put several pieces of gravel orpebblesontopsothattheyjusttouchthelid,andaresurroundedbysand.

2Afteryoupracticethisfirstonyourown,challengeafriendorparenttotrytomovethegraveltotheotherendofoneofthejarswithoutopeningthelid.Letthemtryforawhile,thentellthemitneedsaspecialtouch.

3 Ifyouwant,youcansaysomemagicwords.Thenturnthe jarupsidedownandlightlybangitonthetableoverandover.Thegravelwillslowlyrise.Whenit

getstothetop,simplyturnthejarbackover.

SUPPLIES2narrow,transparentjarswithlids

sand

gravelorpebbles

What’sHappening?Even though thegravelmightbedenser than the sand,whenyoubang the jaragainst the table, the sand flows around the gravel and settles underneath it,forcingthegravelupward.

What does this have to dowithDenali? In cold regions likeAlaska, a similarsortingprocesshappensasfinesoilfreezesandthaws.Whenwetsoilfreezes,itsvolumeincreasesbecauseicetakesupmorespacethanwaterdoes,andthesoilheaves up a little. Then, when the soil thaws and the ice melts, the volumedecreasesandthesoilslumpsbackdown.Thisheavingupandslumpingdownhappensoverandoverandiscalled“frostheaving.”Itisabitlikepoundingyourjaronthetable.Frostheavingforceslargerstonesupwardasthefinersoilflowsaroundthestonesandsettlesunderneath.Italsoforcesthestonesintopileswithsoil in between. This forms “patterned ground,” where larger stones formpatternsofcircles,polygons,orstripes.Itlookslikeahumanartistarrangedthestones,butit’sreallyMotherNatureatwork.

Chapter15

BUCKISLANDREEFNATIONALMONUMENT

HawksbillSeaTurtle

Ifyou’reluckyenoughtovisitBuckIslandReNationalMonument,youwill be enchanted.Buck Island is a small, uninhabited islandoff St. Croix in theU.S. Virgin Islands, a territory of theUnitedStates in theCaribbeanSea.Youcan swim in turquoisewatersorwade in the shallows. An underwater snorkeling trail windsthrough an astonishing array corals and fish. Coral reefs are themost diverse area in all the oceans, and they are built by animalsthataresmallerthanyourfingernail.

CORALREEFSAREONLYFOUNDINWARM,SUNLIT,SHALLOWWATERTHATISATLEAST65DEGREES

FAHRENHEIT(18DEGREESCELSIUS).

Left:PhotoCourtesyofDr.CarolineRogers,USGS

MOSTOFBUCKISLANDREEFNATIONALMONUMENTISUNDERWATER!

WORDSTOKNOWterritory:aregionthatisn’tastateorprovince,butisstillpartofacountry.

organism:somethingliving.

polyp: a small invertebrate animal that often makes a calcium carbonateskeleton.Polypsusuallyliveincolonies,andtheirskeletonsformcoralreefs.

invertebrate:ananimalwithoutabackbone.

limestone: a type of rock consistingmainly of calcium that comes from theremainsofseaanimals.

IT’SAROCK…IT’SAPLANT…IT’SANANIMAL?Afteraquickglanceatacoral,youmightthinkit’saplant,orperhapsarock,butyou probably wouldn’t guess it’s an animal. Actually, corals are animals withmicroscopic algae inside their tissues and theydeposit rock skeletons—so theyare in fact, animals, plants, and rocks, all in one.A coral isn’t an “it,” though,because it’s usually not one organism; it’s a “they”—a whole collection oforganismscalledpolypslivingtogetherinacolony.

Coralpolypsarelikeseaanemoneswithanopening,ormouth,ontopthatissurroundedbyacircleoftentacles.Atthebeginningofitslife,acoralisalarva

aboutasbigastheheadofapinandswimsfreelyinthewater.Butthenitsettlesdownandattachestoahardsurface,nevertomoveagain.Coralpolypsmakealimestoneskeletonfromminerals intheseawater.Theskeletonofonepolypislikeaverysmallcup.Thepolypcanshrinkintothecupwhenthere’sdanger,orextendoutwhenitneedstofeed.

PhotoCourtesyofErinnMuller

ELKHORNANDSTAGHORNCORAL,ASWELLASSOMESPECIESOFSEATURTLES,BROWNPELICANS,ANDOTHER

BIRDSAREENDANGEREDORTHREATENEDATBUCKISLAND.

Coral polyps look gentle, but they are built to kill: the tentacles are packedwithstingersthatcaptureandkillverysmallanimalsfloatingintheocean,calledplankton. The stingers kill the plankton, then the tentacles push the planktonintothecoral’smouth.Coralshaveanothertricktohelpfeedthemselves:insidetheir body they have tiny algae, called zooxanthellae. The coral providesprotectionandnutrientstothealgae,andthealgaeprovidefoodandcolor.Forthealgaetomakefood,theyneedsunlightlikeallplants,socoralshavetoliveinclear,shallowwater.

Coralreefsarebuiltupfromtheskeletonsofthousandsofcoralcolonies.Overhundreds and thousands of years, many coral colonies deposit limestone andgraduallyformreefsthatcanbeasmallpatchorhundredsofmilesacross.

WORDSTOKNOWplankton:smallplants,animals,orlarvaethatfloatfreelyintheocean.

algae:atypeofplantthatlivesinthewateranddoesn’thaverootsorleaves.

zooxanthellae: blue-green algae that live in the tissue of coral polyps.Zooxanthellaecontributenutrients to thecoral,and inreturngetaprotectedplacetoliveinthesunlight.

MORESPECIESOFPLANTSANDANIMALSAREFOUNDINCORALREEFSTHANANYOTHERENVIRONMENTINTHE

OCEAN,ANDPOSSIBLYMORETHANANYOTHERENVIRONMENTONEARTH!

Depending on the type of coral, the polyps and their skeletons form a greatvarietyofcorals.Here’swhatyoumightseeatBuckIslandReef:

ElkhornCoral:large,flattenedbrancheslookremarkablylikethehornsofamoose.Theygrowfairlyquickly—severalinchesinayear.

StaghornCoral:cylindricalbranches.

StarCoral:mostcommoncoralindeeperwater.

Brain Coral: massive, round corals that have curved grooves on theirsurfacelooklikethefoldsofahumanbrain.Braincoralsgrowslowly,buttheyareverysturdy.

ElkhornCoral

StaghornCoral

BrainCoralMiddleandBottomPhotos:PhotosCourtesyofDr.CarolineRogers,USGS

READYFORYOURTEETHCLEANING?Ifyou’reafish,andyouhaven’tseenadentistlately,it’stimeforacheckup.Youcan get one at a coral or sponge, where a cleaning specialist, such as theSharknoseGoby, can cure all sorts of problems. The gobywill pick off deadscales,bacteria,andsand,andcleanoutanycutsor infections.Thenit’s timeforyourteethcleaning.Thegobyswimsrightintoyourmouthtopickoffdirtandbacteria.Thebest part? It’s free.The gobygets a free lunchby eating allthoseyummymicrobes.Don’tgotoooften,though.Ifyoudon’thaveenoughdeadscalesandbacteria,thecleanerswilltakelittlebitesfromyouinstead!

WORDSTOKNOWbacteria:asingle-celledorganism.

microbe:averysmalllifeform.

BUCKISLAND’SSEATURTLES

BUCKISLAND’SSEATURTLES

HawksbillSeaTurtle

BuckIslandReefprovidesanimportanthabitatforseaturtles.Theleatherback,hawksbill(bothendangeredspecies)andgreenturtle(athreatenedspecies) all nest and forage for food at Buck Island.Hawksbill turtles have abeautiful, “tortoise-shell” shell that is prized for jewelry.As a result, they arethemost seriously endangeredof the turtles, andBuck Islandhasoneof themost important concentrations of hawksbill turtles in the Virgin Islands.Hawksbillturtlesliveatsea,andcometonestatBuckIslandevery2to4years.Mostfemalesreturntothesamebeacheachtimetheyarereadytolayeggs.

Since1988,biologistshavestudiedthehawksbillseaturtletobetterunderstandhowtohelpitrecover.Theytagtheturtles,sotheirmovementscanbetracked,andpatrol thebeachesnightly. Ifanest is indanger, theycarefullymove thenest.Thehatchlingsneedaclearpathtoreachthesea,andbecomedisorientedbyartificial lights. Soduringnesting season, lights are restricted, andvisitorsaren’tallowedtodigorusebeachumbrellasabovethehighwatermark.

CORALREEFSARETHELARGESTSTRUCTURESONEARTHTHATAREMADEBYAPLANTORANIMAL.

PhotoCourtesyofDr.CarolineRogers,USGS

IT’SAFISHEATFISHWORLD…Everyorganismonacoralreefhastocompeteforspaceandsunlight.Animalsareeitherpredatororprey,andtheyhavedevelopedanamazingbagoftrickstosurvive.HerearesomefishyoumightseeatBuckIslandReef,andsomeoftheirspecialadaptations:

ParrotfishParrotfishbiteandscrapecoralandgrindthesmallpieces intosand to get the algae inside. Some parrotfish species wrap themselves atnightinclearcocoonsofmucousthatcomesfromanorganontheirhead.Scientists think the cocoon masks their scent, making it harder forpredatorstofindthem.

Four-eye butterflyfish have a large dark spot near the tail on each side,surroundedbyawhitering.Thespotslooklikefalseeyes,andtherealeyeshaveastriperunningthroughthem.Mostpredatorsaimfortheeyeswhenthey attack. If the four-eye butterfly fish is attacked, it flees. Since it’sswimming in a different direction than the predator expects, it can oftenescape.

Queentriggerfishprotectthemselvesbyerectingtheirfirstspine,whichislargeandstrong.Thesecondspinelocksthefirstoneinplace—likeatrigger—sotheycan’tbepulledoutoftheirhole,orbeeasilyswallowed.Thequeentriggerfishloveseatinglargeseaurchins,andhasauniquewayofcapturingthesepricklyanimals.Itflipsovertheseaurchinbyeitherpuffingwater,orpicking the urchin up by the spines and dropping it. Once the urchin isupsidedown,thetriggerfishattackstheundersidethathasshorterspines.

Porcupinefish protect themselves by taking in water and inflating like aballoon, making the normally flat spines on its body stick out—not anappealingmeal.

Parrotfish

Four-eyebutterflyfish

QueenTriggerfish

PorcupinefishPhotosCourtesyofDr.CarolineRogers,USGS

PhotoCourtesyofOAR/NationalUnderseaResearchProgram(NURP)

FRAGILE…ANDRESILIENTOver thousands and millions of years, plants and animals adapt to differentstresses by changing their shape, defenses, color, what and how they eat, andmore.Infact, thereasoncoralreefshavesomanydifferentkindsofplantsandanimals is that there is fierce competition for space and sunlight.When livingthingscompete,theydevelopallsortsofwaystogivethemanedge.Coralreefshavesufferedinthepast,andhaverecoveredtobevibrantcommunities.

Rightnowcoralreefsallovertheworldareindanger.Whentoomanystressesare placed on coral reefs too fast,we don’t knowwhether theywill be able toadapt.Someofthefactorsthatleadtodestructionofthereefsare:

Runoff fromlandcarrieschemicalsandsediments.Alotofsedimentscanclogthemouthsofthecoralpolyps,interferingwithcoral’sabilitytofeed.Itcanalsomakethewatercloudy,whichblockssunlightandmakesitharderforthealgaelivinginsidethecoraltomakefood.

Diseases have especially affected thebrains and star corals atBuck IslandReef.

Hurricanes are hard on elkhorn corals. Rough seas can break theirbranches.

Warmwatertemperaturesduetoclimatechangemaycausebleachingofcorals.Bleachingoccurswhenalgaedisappearfromcoralsbecauseofhighertemperatures.Withoutalgaetogivecoralitscolor,thecorallookswhite,orbleached.Coralssometimesrecoverfrombleachingandsometimesdonot.In 2005,warmerwater temperatures causedmany of the elkhorn coral atBuckIslandReeftobleach,withsomedyingasaresult.

Increasedacidlevelsmakeithardforcoralstogetthemineralstheyneedtomaketheircalciumcarbonateskeletons.

WORDSTOKNOWadaptation: the process in which an animal or plant changes in order tosurviveinitsenvironmentoveraperiodofseveralhundredtoseveralthousandyears.

runoff:minerals,chemicalsandotherremnantsfromfarmsandfactoriesthatcollectinriversandlakesandeventuallyreachtheocean.

bleaching:thelossofalgaefromcoraltissues.Itcanbecausedbywaterthatistoowarmorcold.

Overfishingnotonlyreducesthenumbersandtypesoffish,butmayhurtcoralsaswell.Ifpredatorfisharetaken,theremaybetoomanysmallerfish,snails,andfirewormsthatfeedoncorals.Iffishthateatseaweedaretaken,theremaybetoomuchseaweed,whichcompeteswithcoralsforspace.

Damagebytouristscanresultfromboatanchors,touristscollectingcoralassouvenirs,orcarelesssnorkelers.

CORALREEFS:ONEBIGEGGSHELL

“Seashells, pearls, limestone, eggshells, and sand chalk aremadeofcalciumcarbonate.So,ofcourse,arecoralreefs.Coralstakecalciumandotherparticlescalledcarbonate ions inseawaterandmakecalciumcarbonateskeletons.TheacidityofsubstancesismeasuredbypH,whichvariesfrom0to14.AcidshaveapHbelowseven,whilebases,theiropposite,haveapHaboveseven.ApHofsevenisneutral.Theoceanisnaturallybasic,withapHalittleabove eight. When the pH is lowered, there aren’t as many carbonate ionsfloatingaroundandit’sharderforcoralstomaketheirskeletons.Whentherearen’tenoughrawmaterials,thecoralscan’tworkefficiently.

WhatcanlowerthepHoftheocean?Anacid,ofcourse.Whencarbondioxideintheatmospheredissolvesinwater,itmakesaweakacidcalledcarbonicacid.The pH of shallowwaters in the ocean before the Industrial Revolutionwasabout 8.15; the pH is now about 8.05. One theory is that it’s because ofincreasedcarbondioxide in theatmospheredue tohumanactivities.That’sasmall change, but it’s enough tomean that there are lower concentrationsofcarbonateions.Coralscanstillmaketheirskeletons,butit’smoredifficultandnow they aremore sensitive to other stresses, like pollution. The ocean willnever become as acidic as the vinegar in your experiment dissolving theeggshell,butitmaynotalwaysbebasicenough.Scientistsareresearchingthecomplexinteractionsbetweentheatmosphere,theocean,andcoralreefssowecanworktomakesurecoralshavewhattheyneedtoliveandgrow.

MAKEYOUROWNNAKEDEGGS

1Placeyoureggs in thebowl.Try tokeeptheeggs fromtouchingeachother.Fillthebowlwithenoughvinegartocovertheeggs.Setthebowlwhereyoucanseeitbutitwillbeundisturbed.Youcancoveritifthevinegarsmellbothersyou.

2Afterat leastaday,carefully takeout theeggs.Theyshouldbesoftandyoumaybeable to see through themabit. If theeggsaren’t soft,pourout theoldvinegar,puttheeggsbackinthebowl,andcoverwithnewvinegarforanotherdayorso.Youmayalsoseeachalkywhitelayerontheoutside;iftheeggissoft,youcangentlyruboffthisremnantoftheshellunderrunningwater.

3 Hold your naked eggs a few inches above the kitchen sink and then dropthem.Howhighcanyoudropaneggbefore itbreaks?Canyougentlysqueezeyouregg?

What’sHappening?Eggshells are made mostly of calcium carbonate. The egg actually grows themineral shell. Vinegar is an acid, and calcium carbonate is a base.When thevinegarandeggshellcomeintocontact,theyreactandneutralizeeachother,andthe shell is dissolved.Under the shell, the egg is encased in a thinmembrane.Thismembranebecomesrubberybecauseitallowsliquidtopassthroughit.Thatextra liquid, plus the flexiblemembrane, lets you bounce the egg.Watch out,though;ifyoubounceittoohard—splat!

SUPPLIESafewwholeeggs,stillintheirshells

bowl

vinegar

Resources

WEBSITESTOEXPLOREFURTHER…

NationalParkServicemainwebsite.Fromhere,youcanclickonlinkstofindspecificnationalparksandmonuments,aswellaspagesonnature&scienceorforkids&teachers:http://www.nps.gov/

NationalParkService,Nature&Science:http://www.nature.nps.gov/studentsteachers/linkstolearning/index.cfmClickonlinksontheleftaboutBiologyandGeology

TheUnitedStatesGeologicalSurvey(USGS) is theFederal source forscienceabout the Earth, its natural and living resources, natural hazards, and theenvironment.Forgeneralinformationandlinksforgeology,biology,geography,andwater:http://www.usgs.gov/

USGSwebsiteforGeologyoftheNationalParks.Fromthispageyoucanclickon links for specific national parks, aswell as subjects such as plate tectonics,sand dunes, glaciers, volcanoes, and more:http://geology.wr.usgs.gov/parks/index.html

Forinformationonsourcesusedintheresearchforthisbook, includingbooksandscientificpapers,pleasesendrequeststo:

CynthiaLightBrownc/oNomadPress2456ChristianStreetWhiteRiverJunction,VT05001

http://www.nps.gov

http://www.nature.nps.gov/studentsteachers/linkstolearning/index.cfm

http://www.usgs.gov

http://www.geology.wr.usgs.gov/parks/index.html

ACKNOWLEDGEMENTS

Manypeoplehavehelpedwiththisprojectwithideas,reviews,photographs,andcorrections.Anyerrorsaremine,buttherearefarfewerthankstothefollowingpeople: Matt Nyman, University of New Mexico (Plate Tectonics and GrandCanyon NP); Steve Sillett, Humboldt State University, Sarah Koenen, MuirWoods NPS, Mia Monroe, Muir Woods NPS, Robert Lieber, Golden GateNational ParksConservancy (MuirWoodsNM);David Jagnow, Peg LauHee,BatConservation International,MerlinTuttle, BatConservation International,Mary Kay Manning, Big Bend NPS, Kevin Moh, Carlsbad Caverns NPS(CarlsbadCavernsNP);MichaelWiles,JewelCaveNPS,ArtPalmer,JewelCaveNPS(JewelCaveNM);ElizabethHill,CarnegieMuseumofNaturalHistory,DanChure,DinosaurNPS, IanTurton,BrantPorter,DinosaurNPS,CarlaBeasley,DinosaurNPS, (DinosaurNM);WilliamParker,PetrifiedForestNPS,T. ScottWilliams, Petrified Forest NPS, Hallie Larsen, Petrified Forest NPS, (PetrifiedForestNP); Steve Zachary, LassenVolcanicNPS (LassenVolcanicNP); DougOwen,Craters of theMoonNPS (Craters of theMoonNM); LucasGoehring,UniversityofCambridge(DevilsTowerNM);PatrickMyers,GreatSandDunesNPS,CarolSperling,GreatSandDunesNPS(GreatSandDunesNP);EricaBreeRosenblum, University of Idaho, John Mangimeli, White Sands NPS (WhiteSandsNM);DavidEk,DeathValleyNPS,MikeBower,DeathValleyNPS,BobWilliams, U.S. Fish andWildlife Service, Paul Barrett, U.S. Fish andWildlifeService (Death Valley NP); Guy Adema, Carmen Adamyk, Phil Brease, KrisFister, Karen Fortier, TomMeier, DarylMiller, PatriciaOwen, Laura Phillips,RogerRobinson, and LucyTyrell (DenaliNP);CarolineRogers,USGS,ZandyHillis-Starr,BuckIslandReefNPS,ErinnMuller(BuckIslandReefNM).ThanksalsotoMichaelFrome,agreatsoulandfriendtowildplaces,thewonderfulstaffatNomadPress,myagent,CarynWiseman,mycritiquegroup,andmyfamily.

INDEX

Aacid/acidity,17–19,22,54,101–103activities

cavern,22chocolateriftzone,62columns,67crevasses,92earth,8evaporite,79foamyvolcano,58fossil,36glacier,93igneousrocks,68–69mini-canyon,49–50nakedeggs,103petroglyph,42sanddunes,75sortingtrick,94stalactites,28transpiration,15

adaptation,78,100–101Alaska,2,3,86–94algae,96–97,101animals,10,12,20–21,25,29–36,48,74,77–78,83–85,90–91,95–102Arizona,2,37–50asthenosphere,5–8auroraborealis,92

Bbacteria,18,20,24,98bananaslugs,10bats,21,25BuckIslandReefNationalMonument(VI),19,95–102

Ccalciumcarbonate,101–103California,2,3,7,9–15,51–57,80–85carbondioxide,15,17–18,26,102carbonicacid,17–18,102CarlsbadCavernsNationalPark(NM),16–22Carter,Jimmy,87

caverns/caves,16–27,83,85climate,2,11,16,37,45,48,76–77,80–84,86–91,94–95,101Clinton,Bill,71Colorado,3,29–35,70–74ColoradoRiver,43,45–46Congress,3,38,71,87Coolidge,Calvin,17,59–60coralreefs,95–102CratersoftheMoonNationalMonument(ID),6,59–62crevasses,87,89,92crust(earth’s),5–8,54,56,60,62,71,82

Ddaylight,89DeathValleyNationalPark(CA/NV),2,80–85DenaliNationalParkandPreserve(AK),2,86–94desert,16,29–35,37–38,40,48,76–85DevilsHole,83,85DevilsTowerNationalMonument(WY),3,63–69DinosaurNationalMonument(UT/CO),29–35dinosaurs,29–36,41Douglass,Earl,29–31

Eearthlayers,4–8,54,56,60,62,71,82.Seealsoplatetectonicsearthquakes,6–7,38endangeredspecies,85,97,99,101erosion,4–5,17–19,33,38,40,44–50,64evaporation,28,77,79,81,83

Ffish,85,98,100,102forests,9–15,37–42fossils,19,29–36,41–42,44,71,84

Gglaciers,86,88–89,92–93GrandCanyonNationalPark(AZ),43–50GreatSandDunesNationalPark(CO),70–74gypsum,17–19,23–24,27,76–77,79

HHawaiianIslands,7,52HimalayaMountains,7Hoover,Herbert,71,77,81

hydrothermalsystem,54

IIdaho,3,16,59–62igneousrocks,64–65,67,68–69

JJewelCaveNationalMonument(SD),23–27

KKaibabUplift,45–47Kennedy,JohnF.,96

Llandscapeformation,2,4–8,43–44.SeealsoplatetectonicsLassenVolcanicNationalPark/LassenPeak(CA),7,51–57lava,52–57,60–61LechuguillaCave,20limestone,17–20,22,24,44,48,96–97lithosphere,4–8,82

Mmagma,7,44,53–57,60,62,64–67,69,87MammothCaveNationalPark,25mantle,5–8,62,82maps,vi,6McKinley,William,89minerals,17–19,23–24,27–28,37,39–40,48,64,69,76–77,79,83,96,101–103SeealsosilicaMountMcKinley,86–91MountSt.Helens,7,53mountains,4,7,82.SeealsospecificmountainsbynameMuir,John,14MuirWoodsNationalMonument(CA),2,9–15

Nnationalmonuments,1,3nationalparks,3NativeAmericans,35,39,42,65–66,89Nevada,3,80–85NewMexico,3,16–22,76–79northernlights,92

P

PaintedDesert,40,42PetrifiedForestNationalPark(AZ),37–42petroglyphs,35,42pictographs,35plants,9–15,20,33–34,37–42,48,71–72,74,77–78,82–84,96–97,101platetectonics,2,4–8,43–44,50,54,56,64,71,82,87–88pollution,26,101–102Powell,JohnWesley,48President,3.Seealsospecificpresidentsbyname

Rradiometricdating,67rainfall/rainwater,17–19,24,40,45,71–72,77,81–83RedwoodNationalPark,14redwoodtrees,9–15rifting/riftzones,6,44,50,60,62,71RingofFire,7,56rocks.Seealsolimestoneageof,67

incoralreef,96–97inDevilsTower,63–67formationof,6,16–19,43–45,55,60–61,64–67fossilsin/fossilized,33–34,38–42asglacialtill,88ofGrandCanyon,43–50igneous,64–65,67,68–69imageson,35,42sedimentary,33,47,64

Roosevelt,Theodore,3,10,24,38,40,44,52,64

Ssalt,17–18,79,83–84SanAndreasFault(CA),7sanddunes,70–78,83scientists,6,13,18,20–21,29–31,34,41,45–47,64–67,82,85sedimentaryrock,33,47,64SequoiaNationalPark,14silica,33,39,41,54–56sleddogteam,91SouthDakota,3,23–27speleothems,19,24,27–28spelunking/spelunkers,26–27stalactites/stalagmites,19,28sulfuricacid,18–19,22

Ttectonicplates.Seeplatetectonicstemperature,2,5–7,11,16,45,48,54,80–84,86–91,94–95,101

trees,9–15,37–42turtles,99

UU.S.VirginIslands,3,19,95–102Utah,3,29–35

Vvolcanoes/volcanicash,4,6–7,37,39–40,44,51–58,60–61,65,83

Wwater.Seealsorainfall/rainwater

incaverns,17–19,24coralreefsin,95–102erosionby,17–19,38,44–50evaporationof,28,77,79,81,83inhydrothermalsystem,54forpetrification,37,39plantsuseof,11,15insandduneformation,72,77vapor,15,54–57

WhiteSandsNationalMonument(NM),76–79Wilson,Woodrow,30,87WindCaveNationalPark,25winds,25,33,38,71–73,75,77Wyoming,2,3,63–69

discover national monuments. national parks

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