These are answers to some of the questions from the book homework. i think i got them right, so if I'm wrong, you have my permission to beat me up after school
1. where does the energy come from to cause the movement of tectonic plates?
magma from the core is the reason. it foreces its way up thru the mantle and crust and erupts. it forms sea floor spreading if the preceding happens underwater. SFS is one of the reason the tectonic plates move. the sea floor slowly spreads away because of volcanic cooling
2. what are the current theories of the causes of plate tectonics?
the asthenosphere is kept hot by convenction. it keeps the mantle weak and melty. the heat is from the core. SFS also helps. The floor moves appx. 2 cm/year, but they still move. Dragging also occurs. When cold dense lithosphere sinks, it drags a plate sideways. Lastly "a plate of lithosphere slides down a gentle inclined slope fo asthenosphere"
3. why do so many volcanoes occur aroudn the pacific rim?
The PR or "Ring of Fire," is home to high concentration of earthquakes and voclanoes. at this boudnary, plates are always being subducted. The Pacific Plate comes into contact with many other tectonic plates. This makes it very potent. The subduction melts the crust and forces magma to the surface as volcanoes
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