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hypothesis: Convection CURRENTS IN THE MANTLE drive l ithospere plate movement. Mantle convection animation. Infer: Unequal heating of the mantle material causes rock to flow in convention currents. radiant energy from decay in Earth’s core. e xtruding magma = lava. granite.
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hypothesis: Convection CURRENTS IN THE MANTLE drive lithospere plate movement Mantle convection animation Infer: Unequal heating of the mantle material causes rock to flow in convention currents radiant energy from decay in Earth’s core
extruding magma = lava granite Magma contains minerals that form crystals during cooling basalt Igneous rocks are formed from magma in the lithospherE
• slow to cool • visible crystals Intrusive igneous Cools within the lithosphere gabbro
• Quick to cool • microcrystal formation glassy, even lava magma obsidian Extrusive igneous Cool outside the lithosphere (air/water)
• One magma pool can create both intrusive and extrusive rocks • differ in crystal size, but not chemistry andesite diorite magma One magma pool, two igneous processes
melt/crystallize at a lower temp • Melt/crystallization temp varies from mineral to mineral • As rocks are formed, partial melting can occur, and magma chemistry changes • Next rocks to form reflect new chemistry melt and crystallize at a higher temp One magma pool, chemically different rocks
Plate material heated to 1000F, then cooled, would produce what rock types? 1400 F 800 F One magma pool, chemically different rocks
Magma is defined by it’s silicate – SiO2 - concentration • basaltic – lowest SiO2, <50% basalt • andesitic – medium SiO2partial melting of basalt and granitic • granitic– highest SiO2,>70% rhyolite andesite Major magma types