GEO 101 Chapter Notes - Chapter 13: Gabbro, Inner Core, Asthenosphere
13 Nov 2017
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Document Summary
The lithosphere and plate tectonics: structure of the earth, geologic time scale, major relief features of land and oceans, plate tectonics. Inner core, outer core: upper and lower mantle, crust. The core: contains iron and nickel, around 3500km in radius, earth as a whole is 6400km in radius, the inner core is solid because of high pressures, the outer core is liquid because it"s at lower pressure. The mantle: around 2900km, composed of mafic minerals, lower mantle is solid, upper mantle is soft just beneath the crust. The crust: mohorvicic discontinuity (moho): contact between crust and upper mantle. It is discontinuous (there are gaps: lithosphere is fragmented into lithospheric plates (or tectonic plates, moves over the asthenosphere, asthenosphere: layer of soft, plastic rock in the mantle. The earth is around 4. 6 billion years old. Lithospheric plates: there are 7 major plates and many smaller ones, plate tectonic movement: proposed that convection cells within the earth"s interior drag the crust along.
