ERS120H5 Final: Summarized ers exam review.docx
Document Summary
Formation of solar system: nebula forms from hydrogen, helium after big bang causing nebula to condense into swirling disc with central ball surrounded by rings. Centre ball = the sun, while rings the dust particles collide and become planetesimals which comes proto-earth. Gravity reshaped proto-earth into sphere and interior becomes core and mantle. Small planet later collides with it creating debris around earth ring of debris = forms moon. Crust(10-70km): oceanic basalt and gabbro, thin ; continental mafic and felsic, oxygen most abundant element. Definition of planet: orbits sun, pull self into circle shape, has clear neighbourhood from its orbit. Continental crust: low density, 35 km thick ; oceanic crust: 10 km, high density , Lithosphere(crust and upper mantle) : 100-250 km , hard, thin, cool, can be broken into large fragments called plated ; asthenosphere(upper mantle) : 200 km , ductile (easily deformed), hot, weak, plates float on asthenosphere. Isostasy: plates float at elevation depending on thickness and density.
