GEOL 101 Lecture Notes - Lecture 11: Headwall, Seismic Wave, Seismology
Document Summary
Outline and describe the different types of fault. Explain the difference between hypocenter and epicenter. Explain how seismographs work and how seismologists locate earthquakes. Explain where earthquakes form and the relationships to plate boundaries. Natural hazard: phenomenon with potential to cause death/damage. Earthquake, volcano, flood, storms, landslides, mass wasting. Natural disaster: when natural hazard causes significant damage to life/property. Earthquake: natural hazard caused by rupture (movement) along a fault. Fault: fracture within the earth, across which sliding, displacement, occurs. Rock reaches yield strengths, ruptures and causes an earthquake. Once rocks reaches yield strength, it ruptures and causes an earthquake. Dip-slip fault: movement along fault up and down. Thrust: headwall moves up, horizontal compression at a <30 . Strike-slip fault: movement of two blocks sliding past each other, horizontal movement, shearing of the fault. To describe faults geologists adopted terminology from miners. Headwall: block of rock above fault plane. Footwall: block of rock below fault plane.