Geography 2152F/G Lecture Notes - Lecture 7: Aseismic Creep, Regional District Of East Kootenay, 1906 San Francisco Earthquake
31 May 2016
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Document Summary
Result from the rupture of rocks along a fault. Energy from an earthquake is released in the form of seismic waves. They are mapped according to the epicenter; the focus is located directly below the epicenter. They are measured by seismograph and compared by magnitude. The magnitude of an earthquake can be expressed as a number to one decimal place. This type of measurement was first developed by richter in 1935 (we do not currently use this scale despite people in the media referring to it) The richter scale was a measure of the strength of a wave at a distance of 100km from the epicenter. Since then, more accurate methods have been developed; richter scale no longer in use. Earthquakes are measured using the moment magnitude scale (m) The scale is determined by: the area ruptured (impacted/breakage) along a fault, the amount of movement along the fault, the elasticity of the crust at the focus.
