Geography 2152F/G Lecture Notes - Lecture 7: Richter Magnitude Scale, Logarithmic Scale, The Strongest
17 Nov 2015
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Document Summary
Earthquake magnitude: the magnitude of an earthquake is expressed as a number to one decimal place, this type of measurement was first developed by richter in 1935, the richter scale was a measure of the strength of a wave at a distance of 100 km from the epicenter, since then, more accurate methods have been developed and the richter scale is no longer in use. Earthquake processes: earthquakes are most common at or near plate boundaries, motion at plate boundaries is not usually smooth or constant, friction along plate boundaries exerts a force (stress) on the rocks, exerting strain or deformation, when the stress exceeds the strength of the rocks, there is a sudden movement along a fault, the movement (or rupture) starts at the focus and propagates in all directions, called seismic waves, thus, faults are considered seismic sources.
