Ch.5, Sec.1 - What Are Earthquakes? seismology – the study of earthquakes. - the largest & most active earthquake zone lies along the plate boundaries surrounding the Pacific Ocean. What Causes Earthquakes? deformation – the bending, tilting, and breaking of the Earth’s crust; the change in the shape of rock in response to stress.
Ch.5, Sec.1- What Are Earthquakes? - rock along a fault deforms in a plastic manner (molded clay) or in an elastic manner (rubber band). - plastic deformation does not cause earthquakes! - elastic deformation can cause earthquakes! elastic rebound: the sudden return of elastically deformed rock to its undeformed shape. Elastic Rebound video - during elastic rebound, energy is released in the form of seismic waves & these cause earthquakes.
Ch.5, Sec.1 - What Are Earthquakes?
Ch.5, Sec.1 - What Are Earthquakes? Faults at Tectonic Plate Boundaries Plate Motion Major Fault Type Transform strike-slip Convergent reverse fault Divergent normal fault How Do Earthquakes Travel? seismic waves: waves of energy that travel through the Earth, away from an earthquake in all directions.
Ch.5, Sec.1 - What Are Earthquakes? - seismic waves that travel through Earth’s interior are called body waves. - two types of body waves are P waves (pressure or primary) & S waves (shear or secondary). Pg.134 P waves: waves that travel through solids, liquids, and gases that cause particles of rock to move in a back-and-forth direction. (fastest type) S waves: waves that travel slower than P waves and shear rock side-to-side. - surface waves also occur & are very destructive!
Ch.5, Sec.1 - What Are Earthquakes?
Ch.5, Sec.1 - What Are Earthquakes?