Himalaya Animation - This animation illustrates the process of strain build up and release associated with megathrust earthquakes along the Himalayan front. During quiet times in between earthquakes (interseismic periods), the indian crust is slowly pulled under the Himalaya (at about 2 cm/year=0.8 inches/year). There are places where the plates stick together (locked) and places where they don't (creeping). At locked zones, the lower plate pulls the upper plate down with it, causing the land to subside. Stress at the locked zone builds. When the stress becomes too great, the upper plate breaks free and springs back, causing the Himalayan wedge to suddenly pop up, an earthquake, and aftereffect such as landslides and liquefaction of the soils in lowland areas. This "seismic cycle" recurs, although recurring earthquakes can be different and the circle duration variable.
Credit: Jean-Philippe Avouac, Caltech Tectonics Observatory; Tim Pyle, Caltech IPAC
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