(Original post by smellycat123)
Okay just wrote a plan for a question which could come up for the plate tectonics essay...
"Discuss the extent to which volcanic and seismic events are major factors towards proving plate tectonics theory is valid"
Any feedback would be greaaaat
-Explination of plate tectonics theory.. convection currents created by radioactive decay causing the movement of plate
-where convection currents diverge crust is created, where the converge crust is destoryed etc.
-Lots of evidence to support this theory from Alfred Wegner's findings of 'continetal fit' etc and also the location of seismic and volcanic events largely occouring on plate bounderies
-Majority of volcanic and seismic events follow plate bounderies, e.g pacific 'ring of fire'
-E.g destructive margins such as Nazca plate subducting under South American plate. Volcanic erruptions in the Andes a result of this such as Nivardo Del Ruiz 1985 erruption
-Conservative margins create earthquakes e.g San adreas fault - creating earthquakes in San Fransisco e.g 1989
-Evidence of paleomagnetism at conservetive bouderies, new crust created at these bouderies e.g mid atlantic ridge. This in time creates islands such as Iceland and Surtsey -1965
-Fissure erruptions take place here - basaltic, runny lava... e.g Eijafjallajokul erruption 2010
-Some volcanos/earthquakes occour away from plate bounderies
-Such as central china - earthquakes created by faults.. e.g Longmenshan fault in Sichuan created by stresses in the crust between Sichuan basin and tibetan plateu.
-Some beleive the Sichuan earthquake of 2008 to be caused by the building of zipingpu dam 500m from the Longmenshan fault rather than due to plate movement
-Hot spots found away from plate bounderies
-E.g Hawaii 3000km from the nearest plate boundery ... could suggest plate tectonics theory is not valid
-Other evidence such as continental fit, fossil evidence (mesosaurous), glacial deposits etc
-overall does provide sufficient evidence.. (cant think of a good conclusion!)