If a continental and an oceanic plate were to collide, which plate would go underneath?? Why?
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When two plates collide, they BOTH begin to go under a bit.  However, when a continental, and an oceanic plate collide, the oceanic plate ends up going under more.  Why?\n\nFor one thing, the continental plate is up higher than the oceanic plate to begin with.  After all, continental plates are always above sea level, and oceanic plates are always below sea level.  With the advantage of heighth, the continental plate usually pushes the oceanic plate below.\n\nFor another thing, the continental plate is thicker than the oceanic plate, and therefore is going to be harder to crumple, squish, or flatten.\n\nAlso, the oceanic plate is already under an enormous downward pressure from all of the ocean on top of it.\n\nAdditionally, continental plates are lighter.  They were formed by materials on the primordial earth that had floated to the surface, while oceanic plates are formed out of the magma from the center of the earth, which was below the continental plates because it was heavier at the time the plates were forming.\n\nAnd finally, wet rocks are a great deal softer than drier rocks, so the continental plate is harder to bend or break than the oceanic plate, which is soaked all the way through.
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I think its called 'subduction', where one tectonic plate goes under another. It occurs at 'subduction zones', such as on the west coast of the United States. The reason it occurs is that one plate is expanding and the edges need to go somewhere (under another plate). For example, the Atlantic plate is expanding from the center because there is a north-to-south line of underwater volcanoes, spewing out magma and forcing the 2 halves of the plate apart to the west and east.
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Continental/Continental plate convergence.\n\nThis happens during mountain building episodes called orogenies.
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tectonic plates or continental drift
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Nope; the oceanic plates are spreading apart, as new material (magma) is pushed up from below.  They are not crashing together at all.
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The structural integridy of the plate itself prevents this. When the earth cooled down after its formation the plates were created like large crystals on the molten surface. They can slowly shift around as a result of the magma currents but to have them break would require a large catastrophic event like a meteor or the earth heating up to levels hot enough to lower their integridy. This of course would be a lethal level and would only occur if, for example, the earth got really close to the sun.\n\nThere is the remote chance that an earthquake at just the right fault line might cause just the right fracture that could move through an entire continent but the probability is very remote.
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It is a divergent plate boundary found running down the middle of the Atlantic Ocean. Hence the name "Mid Atlantic Ridge".\n\nThis is where two lithospheric plates are moving apart from each other.\n\nWhere they spread apart, new continental crust is being created. It is said that the US & the UK move about 1 - 2 inches apart every year. The US is getting further from Europe all the time!
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The earth's crustal plates float on a layer called the Mantle, and it is convection in this mantle which drives the continental drift or plate tectonics.
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The plates consist of an outer layer of the Earth, the lithosphere, which is cool enough to behave as a more or less rigid shell. Occasionally the hot asthenosphere of the Earth finds a weak place in the lithosphere to rise buoyantly as a plume, or hotspot. \n\nOnly lithosphere has the strength and the brittle behavior to fracture in an earthquake. \n\nThe map below locates earthquakes around the globe. They are not evenly distributed; the boundaries between the plates grind against each other, producing most earthquakes. So the lines of earthquakes help define the plates: \n\n\nIn cross section, the Earth releases its internal heat by convecting, or boiling much like a pot of pudding on the stove. Hot asthenospheric mantle rises to the surface and spreads laterally, transporting oceans and continents as on a slow conveyor belt. The speed of this motion is a few centimeters per year, about as fast as your fingernails grow. The new lithosphere, created at the ocean spreading centers, cools as it ages and eventually becomes dense enough to sink back into the mantle. The subducted crust releases water to form volcanic island chains above, and after a few hundred million years will be heated and recycled back to the spreading centers.
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In geology it's typically subduction; two tectonic plates are colliding with one diving under the other.
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The reponse is related to plate tectonics. The earth crust is composed of a larger number of plates that float, very slowly of course, over the liquid interior. Continents therefore move relative to each other. When two plates meet, generally one moves under the other and it is here that we find mountains and volcanoes.\n\nWhat relation with oceans? Well, between some of the plates there is an upwelling of new magma, new crust. This is for instance the case in the middle of the Atlantic Ocean. The new crust needs room and pushes the plates on the left and right away: the Americas are moving to the west, while Europe and Africa are moving to the east. \n\nOceans (ah, at last!) are watermasses in which such upwelling of fresh crust takes place. An ocean therefore is partly in two or more different plates. On the other hand, seas are bodies of water that are on one continental plate only, or on two plates were no new crust is formed.\n\nHere is a pictures of the different continental plates:\n http://en.wikipedia.org/wiki/Image:Plates_tect2_en.svg
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Subduction zones occur where oceanic crust collides with continental crust.  Since oceanic crust has more density, it is always subducted underneath continental crust.
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About 1,800 miles beneath the surface, Earth's internal structure changes abruptly where the solid rock of the mantle meets the swirling molten iron of the outer core. \nBut the boundary between the core and the mantle may not be as sharply defined as scientists once thought. By analyzing earthquake waves that bounce off the core-mantle boundary, researchers have found evidence of a thin zone where the outermost core is more solid than fluid.\n\nThe existence of such "core-rigidity zones" -- small patches of rigid material within the fluid outer core -- has been suggested before, but this report marks the first time scientists have detected one.
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Movement of the tectonic plates resulted in the breaking up of "Pangea", the super continent. Here is more information for you including a video clip on the last link. The video takes a bit to load.\n\nHave fun!
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Not exactly pressure.  Tectonic plates under the Earth's crust are constantly in motion.  When they collide, mountains are formed.  These mountains become volcanoes when the tectonic plates hit each other and then move further apart, therefore creating a direct channel to the molten core of the earth.  When the molten material builds up it shoots up the hole of a volcano.
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1. Continental drift or plate tectonics.\n\n2. Horizontal fault line.
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The process as a whole is known as 'continental drift,' or 'plate tectonics'. This process is further divided into several processes: divergence, or where plates are moving away from one another as a result of lava welling up and cooling in a mid-ocean ridge; convergence, where two plates collide and either form mountains or subduct depending on their types; and transformance, where tow plates move at opposite directions parallel to one another. \n\nKnowing this, your question can be answered. You are describing convergance between either two oceanic plates or one oceanic plate + one continental plate. The process is also known as subduction, and can form large mountains and volcanic/seismic activity.