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Rocks and Minerals II. http://www.geology.wisc.edu/~maher/air/air14.htm. Rock Types. Igneous Sedimentary Metamorphic . Rock Types - Igneous. Igneous means “formed from fire” Rocks formed by cooling and crystallization of molten material called magma
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Rocks and Minerals II http://www.geology.wisc.edu/~maher/air/air14.htm
Rock Types • Igneous • Sedimentary • Metamorphic
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)
Rock Types - Igneous Granite Gabbro http://seis.natsci.csulb.edu/basicgeo/GABBRO/gabbro_handsample_labelle.jpeg http://seis.natsci.csulb.edu/basicgeo/GRANITE/Granitic_Minerals.jpeg Obsidian Lunar basalt http://volcanoes.usgs.gov/Products/Pglossary/obsidian.html http://www.lpi.usra.edu/expmoon/Apollo15/A15_BasaltFS.gif
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
Rock Types - Sedimentary fossiliferous rock http://physics.uwstout.edu/geo/gallery http://www2.vscc.cc.tn.us/svinson/geo100/sedimentary.html Andrew Alden sandstone conglomerate
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.
Rock Types - Metamorphic Quartzite Gneiss Gneiss http://www.mii.org/mineral_photos_by_type.htm http://www2.vscc.cc.tn.us/svinson/geo100/metamorphic.html
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.