ENVS 1050 Lecture Notes - Lecture 9: Lithosphere, Indep, Passive Margin

• School: University of Guelph
• Department: Environmental Sciences
• Course: ENVS 1050
• Professor: Don Cummings

Document Summary

Conductive heating- transmits heat slowly by molecular agitation without bulk motion of the material. Convective heating- transmits heat rapidly by bulk motion of the material. *becaue it has a very high raleigh number. *it is very thick, helps maintain that requisite density imbalance. *the temp contrast between its bottom and top is substantial. *spreading ridges can migrate rapidly across the earths surface. *some plates are bordered almost entirely by spreading ridges. *spreading ridges push the litho. plate outward, and gravity pulls the litho. plate downward into the mantle. Earthquakes and faults are con ned to the lithosphere because. *the lithosphere can deform by brittle failure whereas the mantle that underlies it cannot! *benioff zones are dipping planar ones of increased earthquake activity caused by subduction of one tectonic plate beneath another. *because subduction does not occur at continental-continental convergent plate boundaries. *places of mantle convection indep. of plate tectonics.