Mineral Formation3.3

website with video clips

http://nature.berkeley.edu/classes/eps2//wisc/Lect3.html#hydrot

Where do minerals form?

• Evaporation

• Deposition

• Igneous

• Pegmatites

• Metamorphism

• Groundwater

Evaporation

• Salt water dries up in lakes & seas

• Salts left behind

• Ex: halite, gypsum• Photo is Gozo Island, Malta

http://www.stockphotos.it/image.php?img_id=10574146&img_type=1

Deposition

Rocks get dissolved by g.w.

Water flows downstream

Minerals crystallize

Ex: calcite, dolomite

http://www.collecting-rocks-and-minerals.com/how-are-minerals-formed.html

http://www.treeworld.info/f36/castaic-mine-trip-15862.html

Igneous

• Magma that slowly cools beneath the surface

• Crystals form from elements in magma

• Ex: mica, magnetite, quartz, hornblende (in photo)

http://www.indiana.edu/~geol105/1425chap5.htm

Pegmatites

• Magma that squeezes through rock

• Slowly cools & minerals crystallize

• Ex: topaz, tourmaline

http://scienceblogs.com/highlyallochthonous/2008/07/larger_than_your_average_mica.php

Metamorphism

• Minerals in any rock that are subjected to high T & P

• Undergo chemical rearrangement

• Ex: calcite, garnet, graphite, magnetite, talc, mica

Groundwater solutions

• GW moves down & gets heated

• Minerals in magma & rocks get dissolved

• Water flows through cracks

• Minerals crystallize

• Ex: gold, copper, pyrite, galena, azurite

sciencephoto.comcrystalinks.com

Resource Use

• Ore = economically valuable deposit of minerals

• Coal, gravel, & sand are included as resource…but remember…technically they are not minerals

Mining

• Surface = open pit– Create extensive water pollution

• Kennecott Copper Mine UT…world’s largest open pit mine

Mountaintop Mininghttp://www.ohvec.org/galleries/mountaintop_removal/007/

Mountaintop removal of coal has changed the Appalachian mountains

Mining

• Subsurface

• Tunnels & shafts are dug to allow mining under the surface of the earth

• Potentially dangerous

eastenergyinc.com undergroundmining.blogspot.com

Reclamation

• Attempt to return the land to original state

• Mountaintop removal area this is impossible, because we’ve crushed & hauled away the mountain!

• Ecosystems are not replaced & replenished.

Homework

• Read pages 74 - 79

Output

• Sketch pictures to represent your personal uses of minerals…a minimum of 10 pictures.

“Minerals and YOU” article

• Read the “Minerals and YOU” article

• Answer the questions