Earth Sciences 2240F/G Chapter Notes - Chapter 4-6: Mercalli Intensity Scale, Seismic Wave, Seismometer
13 Feb 2018
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Document Summary
Earthquakes and their consequences are in the top 10 worst natural disasters in history. Earthquake (accepted definition): the ground shaking that accompanies sudden movement on a fault: could also be the shaking produced by motion of magma underground, could also be an underground nuclear bomb explosion (rare) Prior to fracturing, rocks respond in 2 different manners when subjected to stress: @ low applications of stress, the rock will deform. As soon as you release the stress, the deformation disappears: response = elastic", if you impose greater stress, the rick will deform to the point that when stress is released, not all the deformation disappears. Plastic/ductile deformation": even greater stress results in rock fracture (earthquake = when the stress is suddenly released) Rocks that are located deeper w/in the grounds surface are more likely to survive more stress before rupturing b/c they have more elasticity than the rocks closer to the surface (b/c they"re warmer)
