GEOL 1250 Lecture Notes - Lecture 6: Continental Crust, Diorite, Gabbro

• School: University of Georgia
• Department: Geology
• Course: GEOL 1250
• Professor: Patino- Douce

Document Summary

Slow cooling produces large crystals: phaneritic texture. Basalt = gabbro 70% of the surface of the earth. Basalt above the surface, gabbro is below. Ex. yellowstone, sierra nevada, along continental margins, super volcanoes. Formed by partial melting of mantle rocks. Needs a lot of heat and energy. Water/simple substances melt in a single temperature and composed of liquid and solid at the same time. Rocks melt in a range - can be both liquid and solid at the same time. Rocks melt over a whole range of temperature. Composition of solid and liquid are different. Entire composition of the rock you started with. Does not matter how you melt it, the composition of the melt is always basalt. What erupts at the surface of the earth is not always basalt. Convection can take place by having something get heated gaster than it can cool down. Mantle is moving up so quickly that the geotherm goes up.