EESA06H3 Chapter 3: Chapter 3
Document Summary
Earthquake: trembling or shaking of the ground caused by the sudden release of energy stored in the rocks beneath the earth"s surface: stress force, strain bend/change shape. Seismic waves: waves of energy released and sent through the earth, produced by an earthquake: fault break between rock masses past each other along a fault (vertical, horizontal, or both) Indonesia and sumatra earthquake (2004) is the largest earthquake (magnitude of 9. 3) Focus (hypocentre): point within the earth where seismic waves first originate; centre of the earthquake, point of initial breakage and movement on a fault. Epicentre: point on earth"s surface directly above the focus. Two types of seismic waves: body waves: seismic waves that travel through the earth"s interior, spreading outward from the focus in all directions (within earth) P wave: compressional/parallel wave in which rocks vibrate parallel to the direction of the direction of wave propagation (fast)
