Geology 101 - Lecture 20
Earthquakes
Determining structure of the Earth from Seismic Waves
- Can liken shaking a Christmas present to "discovering" Earth's
internal structure
- Wave refraction of P and S waves creates curved ray paths
- S waves do not travel through liquid (i.e., liquid outer core).
They get absorbed and cannot pass through
- Get wave "shadows" where no waves exist for seismometers to read
due to refraction (P & S waves) and absorption (S waves by fluid in
outer core)
Earthquakes occur on faults
- Relationship between stress (force/unit area) and strain (deformation)
- Relationship between plate tectonic boundary and fault type