RAP 12/17pg 94What is a rock?What are the three types of rocks?

Topic: Rocks Chapter 66.1 How Rocks Form6.2 Igneous Rocks6.3 Sedimentary Rocks6.4 Metamorphic Rocks

How Rocks FormIn this section, we will be answering two questions:What is a rock?What is the rock cycle?

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What is a rock?=group of minerals bound together.

A. Rock Cyclelink

Rock Cycle DiagramTape the Rock Cycle onto page 95 in your notebook.

SedimentaryIgneousMetamorphicRocks!

a. form from crystallization of _____B. Rock Types1. Igneous Rocksmagma

b. ClassificationType of magma-Felsic or Granitic or Rhyolitic-rocks are light colored and have high silica content i.- Mafic rocks are dark colored, have lower silica

Felsic or Mafic? ________________http://itc.gsw.edu/faculty/tweiland/gabbro.jpghttp://www.pitt.edu/~cejones/GeoImages/2IgneousRocks/IgneousCompositions/7Rhyolite/RhyoliteCUp.jpgFelsicMafic

RAP 12/18 (pg 96)The rock shown is composed primarily of large crystals that were formed byCooling magmac. weatheringCompacting shellsd. faultingWhat word would describe the type of magma that formed this rock? Why?

Classifying Igneous Rocksii. Grain size or textureExtrusive rocks are fine-grained.Intrusive rocks are coarse-grained--http://core.ecu.edu/geology/harper/igneous/I15lg.gif

two types: -______________-lava cools quickly on Earths surface, small crystals (fine-grained)

-________________-lava cools slowly underground, large crystals (coarse-grained)

Classifying Igneous RocksExtrusiveIntrusive

http://cc.usu.edu/~sharohl/glossary.html

Intrusive or Extrusive?___________________________________volcano.und.nodak.edu/.../volcanic_rocks.html

What are the two main ways petrologists classify igneous rocks?If you find a rock that is dark with large grains, what 2 terms would you use to describe it?If you find a light rock with large crystals, what 2 terms would you use to describe it?If you find a light rock with small crystals, what 2 terms would you use to describe it?

RAP 1/2 pg. 96Welcome Back!What two processes would occur to change a metamorphic rock to an IGNEOUS rock?

2.

RAP 1/3 pg. 96How do metamorphic rocks form?What two ways are metamorphic rocks classified? (hint-use your essentials)

2. Metamorphicchanged by ___________ and ___________

Types of metamorphism

RegionalContactHydrothermal

heatpressure

www.gly.fsu.edu/.../ 7_Rocks/7_Rocks_index.htm1. Regional Metamorphismaffects large regions of the Earths crustmost often generated by the compressive forces of mountain building

http://enterprise.cc.uakron.edu/geology/natscigeo/Lectures/smrocks/metafig.gif2. Contact Metamorphism3. Hydrothermal Metamorphismhttp://www.uoguelph.ca/~sadura/metref/met19.gifoccurs when solid rock comes in contact with molten rock solid rock, usually from an ________ intrusion.occurs when very hot water reacts with rock.

igneous

Places where metamorphic rocks can form.

Formation of metamorphic rocksPressure from the weight of overlying rocks

b. Texturesi. Foliated

ii. Nonfoliated

i. Foliatedfoliated : wavy layers and bands of minerals high pressure during metamorphism, can cause flat or needle-like crystals to form

Ex_________: alternating bands of light and darkGneiss

Photo courtesy of Claude G. Genest, University of Quebec at http://www.uqtr.uquebec.ca/relief/Terme/Photo/IMG0054.jpgGneiss Rocks!

GneissGneiss

Mineral Changes During FoliationDiagram courtesy of Dr. Jrgen Schieber, Indiana University, at http://www.indiana.edu/~geol105/images/gaia_chapter_5/foliation.jpg

Foliation: SlatePhoto courtesy of David L. Ozsvath, University of Wisconsin, at http://www.uwsp.edu/geo/faculty/ozsvath/images/slate.jpg

You dont know schist!Granite schist with garnet porphyroblastshttp://www.otago.ac.nz/geology/features/rocks-minerals/schist-gnt.jpg

Schist happens!http://www.gc.maricopa.edu/earthsci/imagearchive/DK_MICA_SCHIST_big.jpg

ii. Nonfoliated-Blocky crystal shapesExample: Quartzitehttp://www.physci.wsc.ma.edu/young/pgeol/geoinfo/images/rocks/quartzite.jpg

ShaleSlatePhylliteSchist

Parent rocks and their metamorphic babies.

Do Now 12/17Using the chart above: Rocks subjected to high temperature and pressure during metamorphism, can form ______.What are two possible parent rocks of gneiss? What does limestone turn into when it undergoes metamorphism?

Metamorphic Mini lab

RAP 1/4 pg. 98Schist is a type of _______ metamorphic rock.

Marble is a type of ______ metamorphic rock.

Granite is a type of _______ igneous rock.

Pumice is a type of ______ igneous rock.

3. Sedimentary Rocksa.formed from sediments, dissolved minerals, and/or materialsorganic

b. Process of formation: i. Weathering-the breaking down of rock into smaller pieces by and processesphysicalchemical

ii. Erosion-the movement of sediments

- of sediments by overlying layers squeezed out excess space and water

occurs as dissolved minerals cement sediment grains togethercompactioncementationandiii. Lithification- process of turning sediments into rock

c. Types of Sedimentary Rock Clastic

Nonclastic

-formed from fragments of other rocks or organic material - classified by size and shape of fragmentsSediment SizeRock ExampleGravel2mm

0.063 2mm0.004 0.063mm

Clastic Formation Animationhttp://www.classzone.com/books/earth_science/terc/content/visualizations/es0605/es0605page01.cfm?chapter_no=visualization

ii. Nonclastic

-form from dissolved minerals coming out of solution by or

-fine-grained unless they are crystallizedevaporationprecipitationLimestone (chalk)

Precipitated Mineral: Death Valley

RAP 1/7 pg. 98What are the two types of sedimentary rocks?A rock made of pieces of sand would be which type of sedimentary rock?

By the end of class I willBe able to use sedimentary, metamorphic and igneous features to describe past environments.Be able to sort rocks into their rock type based on their characteristics.

TuffOne other by-product of a volcano is tuff.Tuff is formed when volcanic ash from a volcano is buried and compressed.

Rock FeaturesA. Igneousi. DikeA dike is a sheet of igneous rock that cuts across rock layers vertically at a steep angle.A dike forms when magma intrudes into angled cracks.A dike can be hundreds of kilometers long, and anywhere from a centimeters to many meters thick.

Igneous Formationsii. SillA sill is a sheet of igneous rock that lies parallel to the layers it intrudes.A sill is formed when magma is forced between, not across, rock layers.A sill can be hundreds of meters thick, and many kilometers long.

Sill

iii. Batholiths-large mass of rock that form the core of many mountain ranges.Batholiths are usually made of granite.Batholiths are exposed through the uplift and erosion of overlying rock layers.

Batholith

Igneous FormationsLaccolithsA laccolith occurs when magma bulges upward to form a dome

Laccoliths

Igneous FormationsVolcanic NeckA volcanic neck is left after an inactive volcano erodesA volcanic neck is the central plug of hardened magma

Volcanic Neck

What formations do you see?154326

Sedimentary Features!*** Sedimentary rocks often have evidence of past life, or .http://alpha.dickinson.edu/departments/geol/rennie/fish_2.jpgFossils!!!

1. Sedimentary rocks are important for reconstructing Earths past life and climatic conditions. 2. Sedimentary rocks contain valuable resources such as petroleum, coal, iron, uranium, and others. Importance of Sedimentary Rocks

Sedimentary Features!Horizontal layering called bedding

Two types of bedding include:

1. Graded bedding

2. Cross-bedding

Type 1.-

: contains progressively coarser sediments toward the bottom layersSedimentary Features!Graded bedding

Type 2.

contains inclined layers of sediment moving forward against a horizontal surface Sedimentary Features!http://faculty.uaeu.ac.ae/~afarrag/physical%20geology/cross%20bedding%20copy.jpgCross-bedding:

Ripple Marks with embedded halite crystals.www.geosci.unc.edu/.../ SedStructures.html Mudcracks found in Death Valley.

RAP 1/8 pg. 98 What is the difference between a dike and a sill?What underlies the Blue Ridge Mountains?

By the end of class, I will Show what I know on my rocks quiz

List rock types of each Virginia province using a geologic map and describe how plate tectonics helped form these rocks

Rocks in Virginia

RAP 1/9 pg 98Extrusive rocks have small grains because they -a. harden underground.c. contain rare minerals.b. have a rough mixture.d. cool quickly.

Metamorphic rocks result from the a. erosion of rocks b. recrystallization of rocks c. cooling and solidification of molten magma d. compression and cementation of soil particles

3. Lava that cools quickly forms _____ rocks.a. extrusive metamorphicc. intrusive metamorphicb. extrusive igneousd. intrusive igneous

*****Mineral CompositionLight, highMafic or Basaltic*Left: rhyolitic, granitic or felsicRight: Basaltic or Mafic*Fine-grainedCoarse-grainedporphyrytic*Left(intrusive/plutonic)Right(extrusive/volcanic)***************Consist of crystals derived from different compoundsChalk forms from calcite, forms in deep ocean from accumulation of minute calcite plates from micro-organisms

Other types include halite (evaporite) and gypsum*************