ENVS 1050 Lecture Notes - Lecture 8: Seismic Wave, Seismometer, Refraction

• School: University of Guelph
• Department: Environmental Sciences
• Course: ENVS 1050
• Professor: Don Cummings

Document Summary

2 things needed for a seismometer: maximum amplitude. Therefore, earths average density is greater than the density of rocks from earths"s crust which mean there is denser material in earths interior! *the deeper the wave, the faster it travels. Refraction: like a car hitting the soft shoulder of the road, when a seismic wave encounters a media through which it travels more slowly, it will bend (refract) into that media as it slows down. Because seismic waves increase in velocity with depth, seismic ray paths become curved due to refraction as they pass through the earth (they bend away from the earths centre) *p-wave shadow zones* weak p-waves that re ect off the solid inner core of the earth. Gutenberg discontinuity: signi cant chnage in seismic waves (p-waves slowed, s-waves attenuated) at the core-mantle boundary. (when the waves start to bend when it touches the core mantle, slide 27) shadow zone.