Unformatted text preview: Sources of heat- planetesimal and meteorite accretion, gravitational compression, differentiation, decay of radioactive minerals, tidal pull of the Sun and Moon. The crust does not float on a sea of molten rock. Magma Formation – forms in special settings that melt existing rocks. Partial melting occurs in the crust and upper mantle. Melting is caused by pressure release, volatile addition, and heat transfer What is magma made of – magmas have 3 components (solid, liquid, gas)...
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- Fall '10
- Volcanology, Igneous rocks, Basalt