ENV100Y5 Lecture Notes - Lecture 6: Asthenosphere, Plate Tectonics, Refraction

• School: UTM
• Department: Environment
• Course: ENV100Y5
• Professor: Barbara Murck

Document Summary

Scientists learn about the inside of earth through several lines of inquiry. An earthquake is a sudden release of built-up strain energy. Earthquakes occur as a result of the build-up and release of strain energy in blocks of rock subjected to tectonic forces. Ground shaking that accompanies the release of energy caused by fracturing of rocks, due to the strain energy that builds up as a result of plate motion. Fault: rock fracture along which relative movement occurs. Focus: initial point of rupture along a fault. Epicenter: point on the surface directly above the focus. Seismic waves are refracted when they travel more quickly through some layers than through others. S waves are blocked by the outer core because they can"t travel through liquids. Travel paths of seismic waves are the single most important source of information about. Core / made of fe-ni metal inner core: solid / /