GEOSCI 100 Lecture Notes - Lecture 8: San Andreas Fault, Mantle Wedge, Stratovolcano

• School: UW-Madison
• Department: Geoscience
• Course: GEOSCI 100
• Professor: Meyers, Stephen R

Document Summary

*igneous rocks - rocks made from hot magma. -large crystals because they have had plenty of cooling time to form them. *extrusive - rocks on the outside, visible to us. -small crystals because their cooling time is faster. Can"t see the crystals with the naked eye. *2 basic ways to identify rocks texture & composition. *asthenosphere - weak, plastic, it is like silly putty. It is a solid but moves throughout and flows. *olivine - silicate mineral down deep in the mantle. -has silicon in the middle and 4 oxygens around it. -add iron and magnesium to balance the charge. *granite - intrusive igneous rock on the earth"s crust, large crystals. *mafic - ma stands for magneseum, fe stands for iron. *3 ways to melt rock (or create magma) What you find in basalt: add heat, decompression, add water - ex. Add water to table salt it dissolves.