Post on 16-Jan-2016
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