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The Rock Cycle. The processes through which rocks are formed. Igneous Rocks. Form by the cooling of molten rock (either lava or magma) Typically have a texture of random crystals. Iceland - 1980s, Alan Rubin. Eruption of Mount St. Helens - May, 1980 (commercial slide).
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The Rock Cycle The processes through which rocks are formed
Igneous Rocks • Form by the cooling of molten rock (either lava or magma) • Typically have a texture of random crystals
Sedimentary Rocks • Often form when particles weathered from earlier rocks are transported (by streams, wind or glaciers) and deposited as sediment • The sediment is then buried and converted to rock by compression and cementation • Typically have a texture of small rounded particles cemented together
Metamorphic Rocks • Generally form when earlier rocks are subjected to high temperatures and/or pressures (BUT without melting!) • Typically have a crystalline texture, with a pattern to the arrangement of crystals
Mt. Jefferson, Oregon Cascades
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