earth’s surface is made of rigid slabs of rock that move
TRANSCRIPT
Plate Tectonics
Plate Tectonic Theory Earth’s surface is made of rigid slabs
of rock that move
Plate Boundaries Divergent Plate Boundary - where
two plates separate• ex. mid-ocean ridges
Transform Plate Boundary – where two plates slide past each other; results in earthquakes• ex. San Andreas Fault in California
Plate Boundaries Convergent Plate Boundaries –where
two plates collideOceanic/Continental PlateSubduction – when one plate (oceanic) sinks below another (continental); can result in volcanoes and ocean trenches
Continental/Continental Plateresults in mountain building
Plate Motion Tectonic plates on the lithosphere
move due to convection in the asthenosphere • Convection Currents – circulation of material
(liquid rock) caused by differences in temperature and density
Forces Causing Plate Motion Basal Drag
• convection currents drag plates like a conveyor belt
Ridge Push• rising mantle material at mid-ocean ridges
causes plates to move away from the ridge
Slab Pull• when an older plate goes through subduction it
pulls down on the rest of the plate