If the process of forming new oceanic crust was to be upset would it affect the way continents move?
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The continents would stop moving because the same mechanisms that makes new ocean crust is what pushes the plates into ecah other so the whole system would shut down.
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(m)\n\nAustralian and American researchers investigating forces exerted on the Indo-Australian tectonic plate have discovered that the considerable stresses being exerted on the plate could be leading to its breaking up.\n\nARC Professorial Fellow, Mike Sandiford, from the University of Melbourne’s School of Earth Sciences was recently awarded ARC funding for research aimed at understanding the forces that drive the motion of the Earth’s tectonic plates and the distribution of stresses in the Earth’s crust that give rise to great earthquakes such as the magnitude 9 Boxing Day Sumatran quake.\n\nProfessor Sandiford says the research shows that as much as 10 per cent of the huge amounts of energy being created at plate connection points at Sumatra and Java are being transferred back into our plate and causing major stresses.\n\n“This is enough stress to contribute to mild earthquake activity in the central regions of the plate, such as in the Australian continent or central Indian Ocean, and provides us with clues as to why our plate has been slowly breaking up,” he says.\n\n“The Indian Ocean quakes are, in effect, leading to the active rupture of the Indo-Australian plate into separate Indian and Australian plates. This new research provides us with important information about the stresses that are driving this drawn out tectonic plate divorce.”\n\nThe research, which was conducted in collaboration with Wouter Pieter Schellart of the Australian National University and David Coblentz of the Los Alamos National Laboratory in the US, will be published in the journal Geology (27 January).\n\nThe research is also important for understanding why smaller intra-plate earthquakes such as the 1989 Newcastle quake, which occurred nowhere near the edge of the plate, take place. Up to now, why earthquakes occur in apparently safe zones in the centre of plates has not been very well understood.\n\nProfessor Sandiford says, “Earthquakes such as the 1989 Newcastle quake that killed 13 people and caused more than $1 billion in damages are just one manifestation of mild tectonic activity that has been affecting the Australian continent for the last 5-10 million years.”\n\nThe new research shows that stresses originating at points of collision between two plates are being dissipated back into our plate and generating enormous internal stresses.\n\nThe ARC funded project will map the spatial and temporal pattern of this tectonic activity and relate it to the factors that drive the motion of the Indo-Australian plate.\n\n“This research will contribute to our understanding of the factors that drive plate motion, to earthquake risk assessment in Australia and other comparatively stable continental regions, and to the factors that have shaped our distinctive Australian landscapes,” he says.\n\nBACKGROUND INFORMATION\n\nWhat causes tectonic plates to move?\nThe Earth is made up of a series of layers. The outermost layer is called the crust and the innermost is the core. In between lies an area called the mantle (in turn made up of upper and lower mantle), which is arguably the most important when it comes to understanding where big earthquakes occur.\n\nThe outer part of the Earth, comprising the crust and top 100 or so kilometres of the mantle (together called the lithosphere), consists of a collection of eight major plates which almost fit perfectly together. The continents and oceans all lie on these plates, the major ones referred to as the African, Eurasian, Indo-Australian, Antarctic, Philippine, Pacific, Nazca, North American and South American, depending on their geographic location.\n\nThese plates (also referred to as tectonic plates) float on the softer mantle underneath. Convection currents within the upper mantle layer are a major driving force driving plate motion and therefore behind earthquake activity.\n\nThe lower sections of the mantle closest to the molten core of the earth are also the hottest parts of this la
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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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This would be false.\n\nIt has to do w/ convection currents in the mantle. This is the driving force behind plate tectonics.\n\nConvection currents are caused by uneven heating of molten rock in the mantle. As magma rises toward the crust, it becomes cooler & will then sink. As it sinks it will become hotter again causing a current to form.\n\nThis current actually moves the lithospheric plates. In some places where the lithospheric plates are broken they may be subducted but in others they will not. In this case (continental/continental boundaries) neither will be subducted. They will crumple up & deform. Many mountain ranges have been formed through continental/continental crust deformation.
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The Atlantic Ocean is 150-135 million years old.\n\n~~~~~\n~180 Million Years Ago~\nThe supercontinent Pangea began to break up into two continents, Laurasia and Gondwanaland. Laurasia was made of the present day continents of North America (Greenland), Europe, and Asia. Gondwanaland was made of the present day continents of Antarctica, Australia, South America.\n\nScientists believe that Pangea broke apart for the same reason that the plates are moving today. The movement is caused by the convection currents that roll over in the upper zone of the mantle. This movement in the mantle causes the plates to move slowly across the surface of the Earth.\n\nThe huge world-ocean called Panthalassa remained but the Atlantic Ocean was going to be born soon with the splitting of North America from the Eurasian Plate. \n\n~150-135 Million Years Ago~\n150 to 135 million years ago Laurasia was on the move, and as it moved it broke up into the continents of North America, Europe and Asia (Eurasian plate). \n\nGondwanaland was spread apart, too, and it broke up into the continents of Africa, Antarctica, Australia, South America, and the subcontinent of India. \n\nArabia started to separate from Africa as the Red Sea opened up.\n\nThe Atlantic, Indian, Arctic, and Pacific Oceans were beginning to take shape as the continents move toward their present positions. \n\n\n~The Atlantic Ocean~\nThe Atlantic began to form about 150 million years ago, during the Jurassic period, when a rift opened up in the supercontinent of Gondwanaland, resulting in the separation of South America and Africa. \n\nThe separation continues today at the rate of several centimeters a year along the Mid-Atlantic Ridge. Part of the midoceanic ridge system that girdles the world, it is a submarine ridge extending north to south in a sinuous path midway between the continents. \n\nRoughly 930 miles wide, the ridge has a more rugged topography than any mountain range on land, and is a frequent site of volcanic eruptions and earthquakes. The ridge ranges from 1/2 to 2 miles above the ocean bottom.\n\nThe Atlantic Ocean is the second youngest of the world's oceans, after the Southern Ocean.
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The earth's hard surface (commonly called the crust) can be composed of oceanic crust or continental crust.  The two types of crust can form to create plates.  (Refer to plate tectonic theory)\n\nThe creation of the earth's crust can be a result of many processes such as: volcanism (Hawaii/Mt.St. Helens), Rift Zones (Mid-Atlantic Spreading Center), or combinations of the two.\n\nThe boundaries of these plates can convergent (come together), divergent (move apart), or transverse one another (slide past one another). \n\nOne of the most famous boundary between plates is the transverse or strike/slip fault that commonly creates earthquakes in California. The two famous faults are the San Andreas and Hayward faults.  \n\nEarthquakes are simply a build up of forces on these plate boundaries and eventually break.  The "break" is the earthquake  that we feel, the aftershocks can continue after the initial break, but are usually less intense or less strong (see Richter Scale)\n\nTsunamis are the result of deep earthquakes on/or near the ocean floor.  The movement of the fault will move massive amounts of the oceans water table is shifted. This forms a wave that will generate out in all directions.  When the tsunami travels thousands of miles thru the ocean and comes into contact with land it produces large scale waves (anywhere from 20-300+ feet) in height.
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This process is known as plate tectonics. The earth's surface is composed of large 'plates' which gradually move around over time. The movement is driven by convective currents of molten rock within the asthenosphere. Movement begins at the midocean ridges, which are actually larger than continental mountain ranges. As magma builds these ridges the weight of the material, combined with the convective flow causes them to push outward towards the outer parts of the oceanic plates. Some of these plates subduct (go under) the continental plates, or even other oceanic plates. This subduction process lifts continents higher and leads to mountain building. You can see some illustrations here:\nhttp://www.ucmp.berkeley.edu/geology/tecmech.html\nYou can watch animated versions showing the plate motion here:\nhttp://www.ucmp.berkeley.edu/geology/tecmech.html\n\nAs for parts of the earth falling into the ocean, that is just a not-so-serious thing that people say trying to explain plate tectonics. There are zones of continental crust that are rifting, being split apart, and these may eventually move below sea level. Some examples of this are the Great Rift Basin in northern Africa. The Red Sea is a rift zone that has submerged, and the Dead Sea is part of a rift zone. \n\nThese processes are quite slow on our time scale. The Pacific Ocean is spreading about 4-5 cm per year.\n\nAnd if you've ever heard that California is going to fall into the ocean- don't worry it isn't. The boundary between the Pacific Plate and the North American plate is actually within California, but the motion is such that Los Angeles is moving north towards San Francisco. Millions of years from now, Los Angeles may be moved north of San Francisco.
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This is the Wilson Cycle, and it is driven by plate tectonics. \n\nContinents are composed of relatively light weight felsic igneous rocks such as granites and granodiorites. Ocean basins are composed of mafic igneous rocks like basalt and gabbro that are heavier than continental crust. Since the earth's mantle is plastic, these different masses of rock tend to 'float' at different levels. This is called isostacy.\n\nOceanic plate motion originates at the mid-ocean ridges, pushing oceanic plates outward towards the continents. This motion and force is far from being uniform from one ocean basin to another, and is not even consistent along the length of the mid-ocean spreading centers. \n\nWhere oceanic plates meet continental plates there is a convergent plate boundary and generally this leads to subduction of the oceanic plate. There is considerable force however, and the style of subduction does vary. Since the forces that are being applied, as well as the resistance of the continental plates all are varied, there are inequities that cause the continents to move in one direction. Eventually this motion results in a collision of continents called a supercontinent because continents will not subduct under one another. India and Asia, and the Himalayas are a great example of a continental convergent plate boundary. Eventually the convection forces that cause the supercontinent to form will begin rifting it apart again creating new smaller continents. \n\nHere is a model of the Wilson Cycle:\nhttp://csmres.jmu.edu/geollab/vageol/vahist/wilsonsimp.html
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Earthquakes: \nIt all comes down to stress and strain from the interaction of different plates, chiefly at the boundaries. It is not 'the plates rubbing together' as many people say; or at least that's a very simplistic view.\n\nPlate tectonics causes stress on the continents and oceans, all over the surface of the earth. In some places, the stress is very small (usually within the plates). Elsewhere, the stress is high, usually where the plates meet each other. Since each plate moves, when two come in contact, the stress each other. They can push on each other and cause compressional stress, they can pull with extensional stress, and they can slide past or shear each other with tensional stress.\n\nFaulting, causing earthquakes, comes from the fact that this stress is building up all the time, but rocks and continents are strong materials. Just like hitting a rock with a small hammer, you do put stress on it, but a small amount. It would take a sledgehammer to put enough strain (effects and accumulation of stress) to build up and cause breakage. In the earth, the area around an active fault builds up strain from the stress of plate tectonics. Most faults become locked, because of this strength, and thus can not release their strain. Away from the fault, the stress produces very small and slow movement of the rock masses as a whole. Eventually, the strain is too much and the rest of the plate has moved too far and the fault releases the strain build-up all at once in a big stress release called an earthquake. This is called the elastic rebound theory, and it explains most (but not all) movements.\n\nThis is why an earthquake's size is relative to the fault size. The bigger the fault, the bigger the strain build up, and the bigger the release in an earthquake. Subduction zones and collision zones, where large portions of plates actually can rub together as a whole, have the really big earthquakes, like the 2004 Sumatra earthquake. In other plate boundaries, the entire plate boundary does not act together, so the faults become spread out and many faults take up the strain from the tectonic stress, like with the San Andreas Fault in California (it only takes up ~3/4 of the stress between the plates).\n\nEarthquakes are really tricky things; there is still so much we need to learn. As of now, there is no way to predict them, but we can say where the danger is highest and about how long between events.
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Yes, in fact the Pacific Ocean is surrounded by what is called The Ring of Fire, regions of intense volcanic and seismic activity. Earthquakes are generated by the collision of tectonic plates. This can cause fissure in the crust allowing the magma to rise to the surface where it collects in cavities and becomes the source for volcanoes.
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Absoutly, there is a ridge subduction zone off the pacific coast that is moving at a good clip.  We know through laser tomography, that the surface of this subduction zone isn't as smooth as many other fault lines.  We know what will happen as soon as it 'buckles', a huge earthquake, followed, of course by a sub surface wave, making a tsunami.\n\nAs to when, no clue.  The plate at the subduction zone isn't moving at a constant clip, but random.  So hard to say.  Will it happen? Absoutly, when? Dunno.
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Introduction\nPlate tectonics is a relatively new theory that has revolutionized the way geologists think about the Earth. According to the theory, the surface of the Earth is broken into large plates. The size and position of these plates change over time. The edges of these plates, where they move against each other, are sites of intense geologic activity, such as earthquakes, volcanoes, and mountain building. Plate tectonics is a combination of two earlier ideas, continental drift and sea-floor spreading. Continental drift is the movement of continents over the Earth's surface and in their change in position relative to each other. Sea-floor spreading is the creation of new oceanic crust at mid-ocean ridges and movement of the crust away from the mid-ocean ridges.
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Magma, or molten rock located beneath the earth's surface, cools upon reaching the surface to form the crust. This crust is moved away from the location of upwelling by thermal convection currents in the semi-plastic mantle. The crust is then resorbed back into the mantle upon meeting another, less dense (more buoyant) crust. \n\nThere are two types of crust: oceanic and continental. Each are made from different minerals, resulting in oceanic crust being 'heavier' (denser) and thus sinking below the 'lighter' (less dense) continental crust at convergent boundaries. The earth's crust is in a state of constant motion (or, in some places, no motion, but a building up of energy) called plate tectonics. \n\nSee the wikipedia link below for more details. Hope that helped.
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Some are moving away from each other (i.e. their separation is increasing), such as Africa and South America. Some are moving closer together, like North America and Asia. Some places continents or pieces of continents are moving past each other, like in the Pacific Northwest, or in the Afar Triangle in Somalia. Some places are expanding, like Iceland. \n\nThere are lots of ways to measure this, but the first clue that something was going on came from looking at the shapes of coastlines. Look at the coastlines of western Africa and eastern South America. They look like they could fit together, like a puzzle. The rocks match each other on both continents too, as if the two continents were once fit together. \n\nHowever, the big clue that something was going on came from magnetic stripes on the sea floor. As new basalt forms in the middle of the Atlantic, and some other oceans, it pushes out from the central mid-ocean ridge, and cools. When it cools, it sets, taking on a magnetization aligned with the magnetic field of the earth at that moment. However, the earth's magnetic field flips every few thousand years (just like the Sun's does, every 11.5 years or so). This creates a record of magnetic stripes on the sea floor that alternate polarity. When the scientists Vine and Mathews saw this, they knew they had proved that plate tectonics existed, and that the continents were moving (sometimes away from each other, and sometimes towards each other or past each other)
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Convergent boundaries move toward each other - in oceanic/continental convergence volcanic mountains form; the same for oceanic/oceanic convergence except they are usually referred to as island arcs such as the Aleutian Islands off the coast of Alaska; in continental/continental convergence, mountain ranges are formed such as the Himalayas & Appalachians\n\nDivergent boundaries move away from each other making the crust thinner - rift valleys such as that in Africa in continental divergent boundaries; oceanic ridges such as the Mid Atlantic Ridge in the Atlantic Ocean\n\nTransform boundaries slide past each other horizontally & don't really create any kind of landform that I know of. They just offset things like in California w/ the San Andreas fault. It has been known to move fences & rows of trees out of line.
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b) changes\n\nwhen a plate moves it can do a number of things. it can make a mountain, volcano, island, etc.\n\nit doesnt collapse (stupid answer), it wont melt (why would it? all thats happening is a plate moving, that wouldnt melt earth) and it doesnt shrink just because it moves.
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Pangaea is the name of the original super-continent.\n\nPlate tectonics describes how the continents move.\n\nRead here: http://en.wikipedia.org/wiki/Plate_tectonics