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Details Title: Plate tectonics! Description: Mr. Drake Phy. Sci. Total Flash Cards: 49 Created: 04/19/2007 15:48:15	To study from this set of flash cards, or to create your own your own study flash cards, register HERE. If you are already a registered user, CLICK HERE.
Cards Term Name the continental plates. Definition African plate, N. American Plate, S. American Plate, Eurasian Plate, Indian Australian Plate Term What plate is the largest? Definition The Pacific Plate Term Compare the shape of converging and diverging plate boundaries. Definition Diverging boundaries are jagged(faults) while converging boundaries are smoother(trenches). Term What ocean plate is colliding with the South American plate? Definition The Nazca plate. Term Mountains can be classified into what four groups? Definition Plate Tectonic mtns, Folded mtns, Fault Block mtns, and Dome mtns. Term What is a continental margin? Definition The continental shelf and the continental slope. Term What is a continental shelf? Definition Relatively flat area of land that goes up a coast. It is underwater. Term What is a continental slope? Definition The area of land between the continental shelf and the bottom of the ocean. Term How are continental margins classified? Definition As active or passive. Term What is an active continental margin? Definition Margin where there is tectonic movement, earth quakes, volcanoes, etc. Term What is a passive continental margin? Definition Margin where there is no tectonic movement, only erosion and weathering. Term West coast US= A or P? East coast US= A or P? Definition West=A East=P Term What forms at a subduction zone? Definition A trench. Term Which is older, passive or active? Which is wider? Definition Passive margins are older and wider. Term What are the 2 kinds of vertical faults? Definition Normal and reverse(thrust) Term What is a hanging wall? A foot wall? Definition A hanging wall is the half of a vertical fault with an acute angle at the top. A foot wall has an obtuse angle at the top. Term Describe a normal fault. Definition Vertical fault, hanging wall on bottom, foot wall on top. Term Describe a reverse fault. Definition Vertical fault, hanging wall on top, foot wall on bottom. Term When do tilting and uplift occur? Definition When a rock is too hard or something to fault and instead either the whole rock is tilted up or lifted up. Term When does folding occur? Definition When forces come from the sides, causing the rock to buckle. Term What is and anticline? A syncline? A limb? Definition In a fold, the anticline is the top of the curve, the syncline is the bottom, and the limb connects the two. Term What is a fault? Definition A fracture surface along which motion has taken place. Term What is a strike-slip fault? Definition A type of horizontal fault. Ex. San Andreas Fault Term What fuels continental drift? Definition Release of heat and pressure. Term Who was Alfred Wegener? Definition A scientist who was a pioneer in the theory of Pangaea and continental drift. Term What were the two supercontinents that split up Pangaea? Definition Laurasia and Gondwana. Term What sea dived Laurasia and Gondwana and what sea(s) is it now? Definition The Tethys Sea; Mediterranean, Black, and Caspian. Term What is the lithosphere? Definition The crust and the outermost part of the mantle. It is solid. Term What is the asthenosphere? Definition The rest of the mantle. It is soft and liquid. Term Where are convection currents found, in the lithosphere or asthenosphere? Definition In the asthenosphere. Term Why is the only liquid part of the earth the asthenosphere? Definition Because it is too cold closer to the surface and there is too much pressure closer to the core. Term Are all ocean floors the same age? What is the oldest ocean? Definition NO! Pacific plate contains oldest oceanic crust. Term What is an oceanic ridge? Definition A ridge found at two diverging oceanic plates. A rift is formed which allows lava out to form the ridge. Term What are island arcs? Definition Volcanic islands found on the landward side of trenches. Term What is a transform fault? Definition A fault that occurs due to horizontal sliding. Term Name the first two major plate movements that broke up Pangaea. Definition A north-south split(Laurasia and Gondwana) then an east-west split(split up Laurasia and Gondwana). Term What are convection currents? Where do they occur? Definition Currents that circulate heat flow. They only can occur in a liquid or a gas. Term Name the layers of the Earth starting at the center. Definition Inner core, outer core, mantle, asthenosphere, lithosphere. Term What increases as you move farther into the Earth? Definition Pressure, density, temperature. Term Why is inner core solid? Definition Because of immense pressure. Term When there is a divergent junction, are convestion currents rising or falling? Definition Rising. Term At oceanic-oceanic converging boundaries, which plate goes into the subduction zone? Definition The less massive one. Term At oceanic-continental converging boundaries, which one goes down into subduction zone? Definition Oceanic, b/c it is denser. Term Is there a subduction zone when two continental plates collide? What happens? Definition No, but the less massive plate gets tucked under a little. Term What kind of mountains are found at continental-continental plate collisions and why? Definition Sedimentary, b/c there was probably an ocean between the two plate before and it probably had sedimenary rock. It is being pushed up in the collision. Term What are the two types of divergent plate boundaries? Definition Continental rifting and Oceanic ridges. Term What does continental rifting do? Definition Same thing as oceanic rifting but is much harder to form ridges b/c continental crust is thicker and takes longer for rift to get deep enough. Term When there is a convergent junction, are convestion currents rising or falling? Definition Falling Term What geologic features are found at oceanic-oceanic converging boundaries? Definition Subduction zones, trenches, and island arcs.