Rocks and Minerals II

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Rocks and Minerals II
http//www.geology.wisc.edu/maher/air/air14.htm
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Rock Types

• Igneous
• Sedimentary
• Metamorphic

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Rock Types - Igneous

• Igneous means formed from fire
• Rocks formed by cooling and crystallization of
  molten material called magma
• Shows interlocking crystal grains with sharp
  edges (some may have to be seen using a hand lens
  or microscope)

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Rock Types - Igneous
Granite Gabbro
http//seis.natsci.csulb.edu/basicgeo/GABBRO/gabbr
o_handsample_labelle.jpeg
http//seis.natsci.csulb.edu/basicgeo/GRANITE/Gran
itic_Minerals.jpeg
Obsidian Lunar basalt
http//volcanoes.usgs.gov/Products/Pglossary/obsid
ian.html
http//www.lpi.usra.edu/expmoon/Apollo15/A15_Basal
tFS.gif
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Rock Types - Sedimentary

• Rock formed from accumulation of weathered
  materials (sediments)
• May contain fossils may show layering may have
  a conglomerate nature with rounded particles or
  cementation evident may contain only one mineral
  as a result of chemical deposition
• Generally dull in appearance

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Rock Types - Sedimentary
fossiliferous rock
http//physics.uwstout.edu/geo/gallery
http//www2.vscc.cc.tn.us/svinson/geo100/sedimenta
ry.html
Andrew Alden
sandstone
conglomerate
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Rock Types - Metamorphic

• Term means changed form
• Rock formed from pre-existing rocks through the
  action of high heat (no melting) and pressure
• May be very hard and may show crystals but they
  will be in a linear pattern (foliation) or may
  show elongation or folding that results from high
  pressure certain minerals only form in
  metamorphic rocks.

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Rock Types - Metamorphic
Quartzite
Gneiss
Gneiss
http//www.mii.org/mineral_photos_by_type.htm
http//www2.vscc.cc.tn.us/svinson/geo100/metamorph
ic.html
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Rock Cycle

• Rocks can be changed from one type to another
  through natural geological processes.
• The series of processes that comprise these
  transformations is called the rock cycle.

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http//www.cotf.edu/ete/modules/msese/earthsysflr/
rock.html