GEOL 1001 Lecture : Notes Dec 1st
Document Summary
Volcanic outgassing, after the earth-moon system arose ~4. 5 ga ago, created earth"s atmosphere and hydrosphere. The biosphere grew explosively from o2, the waste product of ancient microbial (don"t survive today) communities. A combination of plate tectonics and mantle plume systems helped float low density rocks, creating earth"s continents. That 2% makes up the hydrosphere and biosphere. Density and porosity differences trap petroleum in sedimentary rocks (often between magma and sandstone). I use resources at a rate that exceeds the recycling rate of geologic processes. Mars contains a larger percentage of si than saturn. Gases on earth become liquid or solid at locations beyond the asteroid belt. Impacts make previously solid rock behave like a fluid. The commonness of craters on mars suggests that, unlike earth, it exposes continental-scale regions of ancient rocks. Mars" orbital radius smaller than that of the asteroids (closer to the sun than the asteroid belt).
