EESA06H3 Chapter Notes - Chapter 4: The Crust, History Of Earth
Document Summary
Geophysics application of physical laws and principles to a study of the earth (includes study of seismic waves and earth"s magnetic field, gravity, and heat) Seismic reflection return of some energy of seismic waves to the earth"s surface after waves bounce off a rock boundary. Seismic refraction bending of seismic waves as they pass from one material to another (similar to how light waves bend when passing through lenses of eyeglasses. Crust outer layer of rock, which forms thin skin on earth"s surface. Mantle lies below crust, thick shell of rock that separates crust above from core below. Core central zone of earth, probably metallic and source of earth"s magnetic field. Seismic waves travel faster in oceanic crust than in continental crust. Seismic p waves travel through oceanic crust at about 7 km/sec and through continental crust at about 6 km/sec: average thickness of oceanic crust is 7 km varying from 5-8 km.