GLY 101LEC Lecture Notes - Lecture 5: Continental Crust, Oceanic Crust, Pannotia
26 Sep 2018
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Document Summary
Scientists discovered a layered planet due to earthquakes. We know the phase of the land based on how the waves travel. As we go deeper towards the center of the earth, temp and pressure increase. Continental crust (where we live), it is the thickest (30-70 km). When land crashes together, granite will never go under since it is lighter than the basalt. The crust sinks during ice age due to heavy glaciers. Lithosphere is the earth"s crust and upper part of mantle; brittle solid and where earthquakes occur. Asthenosphere (most plastic layer of the earth), includes the lower part of mantle. It is an elastic solid and flows in convective currents very slowly at a rate of 15 cm/yr. Made of mainly iron, nickel, and other heavy elements. Significantly high temperatures and pressure (4700 celsius, 3600000 atm) Scientists originally thought the earth was like a grape at first and is becoming a raisin.
