
	Where results make sense

Topic: Oceanic plate

Related Topics

Pre Columbian trans oceanic contact

oceanic trench

Oceanic white tipped shark

mid oceanic ridges

RMS Oceanic

Oceanic Whitetip Shark

Oceanic languages

Oceanic and Other Stories

Oceanic Flycatcher

oceanic plate

Oceanic white tipped

oceanic current

In the News (Sat 14 Nov 09)

Northern Trust

Marvin Harrison

Peter Chernin

Gary Locke

Match Play

Penelope Cruz

Mickey Rourke

AR Rahman

Danny Boyle

Hugh Jackman

	Understanding plate motions [This Dynamic Earth, USGS]
		Plate boundary zones -- broad belts in which boundaries are not well defined and the effects of plate interaction are unclear.
		Land on the west side of the fault zone (on the Pacific Plate) is moving in a northwesterly direction relative to the land on the east side of the fault zone (on the North American Plate).
		Oceanic fracture zones are ocean-floor valleys that horizontally offset spreading ridges; some of these zones are hundreds to thousands of kilometers long and as much as 8 km deep.
	pubs.usgs.gov /gip/dynamic/understanding.html (2502 words)

	Plate tectonics - Wikipedia, the free encyclopedia
		Tectonic plates are comprised of two types of lithosphere: continental and oceanic lithospheres; for example, the African Plate includes the continent and parts of the floor of the Atlantic and Indian Oceans.
		Where a dense oceanic plate collides with a less-dense continental plate, the oceanic plate is typically thrust underneath, forming a subduction zone.
		Plate motion is driven by the higher elevation of plates at mid-ocean ridges.
	en.wikipedia.org /wiki/Plate_tectonics (3990 words)

	MSN Encarta - Search View - Plate Tectonics
		Plate Tectonics, theory that the outer shell of the earth is made up of thin, rigid plates that move relative to each other.
		The theory of plate tectonics was formulated during the early 1960s, and it revolutionized the field of geology.
		Tectonic plates are made of either oceanic or continental crust and the very top part of the mantle, a layer of rock inside the earth.
	encarta.msn.com /text_761554623__1/Plate_Tectonics.html (3862 words)

	MSN Encarta - Print Preview - Plate Tectonics
		The second kind of motion, called relative motion, leads to different types of boundaries between plates: plates moving apart from one another form a divergent boundary, plates moving toward one another form a convergent boundary, and plates that slide along one another form a transform plate boundary.
		Early in the plate tectonic revolution, geologists proposed that transform faults were a new class of fault because they “transformed” plate motions from one plate boundary to another.
		As a transform plate boundary cuts perpendicularly across the edges of the continental crust near the borders of the continental and oceanic crust, the result is a system such as the San Andreas transform fault system in California.
	encarta.msn.com /text_761554623___7/Plate_Tectonics.html (1481 words)

	Plate Tectonics : Subduction Zones
		When two oceanic plates collide, the younger of the two plates, because it is less dense,* will ride over the edge of the older plate.
		The older, heavier plate bends and plunges steeply through the athenosphere, and descending into the earth, it forms a trench that can be as much as 70 miles wide, more than a thousand miles long, and several miles deep.
		If the descending oceanic plate is carrying a continent, the less dense continental material cannot sink, so it dives into the trench behind the leading oceanic crust until it gets stuck.
	www.platetectonics.com /book/page_12.asp (337 words)

	CVO Website - Plate Tectonics and Sea-Floor Spreading
		Each plate is about 80 kilometers (50 miles) thick and can be pictured as having a shallow part that deforms by elastic bending or by brittle breaking, and a deeper part that yields plastically, beneath which is a viscous layer on which the entire plate slides.
		The granite or granitelike layer of the continental crust extends beneath the ridge to the vicinity of the trench.
		As the denser plate of oceanic crust is forced deep into the Earth's interior beneath the continental plate, a process known as subduction, it encounters high temperatures and pressures that partially melt solid rock.
	vulcan.wr.usgs.gov /Glossary/PlateTectonics/description_plate_tectonics.html (8248 words)

	Plate Tectonics (Site not responding. Last check: 2007-09-30)
		Plate Tectonics is a theory developed in the late 1960s, to explain how the outer layers of the Earth move and deform.
		Plate tectonics has proven to be so useful that it can predict geologic events and explain almost all aspects of what we see on the Earth.
		These are oceanic ridges where new oceanic lithosphere is created by upwelling mantle that melts, resulting in basaltic magmas which intrude and erupt at the oceanic ridge to create new oceanic lithosphere and crust.
	earthsci.org /teacher/basicgeol/platec/platec.html (1838 words)

	Plate Tectonics
		Theory that the ocean floors are spreading apart and moving away from the oceanic ridges (propelled by thermal convection cells in the mantle) and that ocean crust is created at oceanic ridges and destroyed by subduction in deep ocean trenches.
		Occur in oceanic crust (oceanic ridges) and in continental crust (rift valleys).
		Cold lithospheric plates are dense and tend to sink into the mantle, pulling the rest of the plate with it.
	www.geo.ua.edu /intro03/Plate.html (2149 words)

	10(i) Plate Tectonics
		Oceanic crust is destroyed at areas where this crust type becomes subducted under lighter continental crust.
		In this type of a collision, one of the plates is subducted under the other creating a deep oceanic trench.
		In this illustration, the oceanic plate subducts under the lighter continental plate.
	www.physicalgeography.net /fundamentals/10i.html (1008 words)

	[No title] (Site not responding. Last check: 2007-09-30)
		Plate Tectonics and Earthquake Potential of Spreading Ridges and Oceanic Transform Faults revision of 6 July 2001 Peter Bird Yan Y. Kagan David D. Jackson Department of Earth and Space Sciences University of California Los Angeles, CA 90095-1567 pbird@ess.ucla.edu (310) 825-1126 Abstract.
		At any point on the boundary between plates i and j, the horizontal part of the relative plate velocity is, where is the relative angular velocity vector (Euler vector) for this pair of plates and is the location vector measured from the center of the Earth, which is approximated as spherical.
		The Macquarie Ridge event was a plate boundary event, but it occurred in lithosphere of unknown age which may be continental, and it was either in or immediately adjacent to a subduction zone on the same plate boundary, and its low-frequency mechanism had a thrust component [Ihml, et al., 1993].
	moho.ess.ucla.edu /~kagan/bird.txt (7294 words)

	Ocean 540: Oceanic Lithosphere; Plate Tectonics; Seafloor Topography
		Motion of the lithospheric plates in the context of convection of the upper mantle.
		Plate tectonics is a modern idea, taking hold as the central paradigm of earth sciences in the late 1960s.
		The upper most lithosphere is the oceanic crust, which is constructed of melt from the mantle which is intruded into pre-existing crust and erupted onto the seafloor.
	www2.ocean.washington.edu /oc540/lec01-1 (1472 words)

	AGU Web Site: Oceanic Plate Motion
		For oceanic plates, such as the Pacific plate, rock exposures are limited to a few young islands.
		The highs and lows are produced by the upper portion of the oceanic lithosphere, which becomes magnetized parallel to the ambient field direction upon its formation at a seafloor spreading center.
		The additional asymmetry in an anomaly caused by anomalous skewness is thought to arise from non-vertical reversal boundaries in the oceanic lithosphere or from lateral variations in the magnetization intensity within a polarity interval.
	www.agu.org /sci_soc/acton.html (1109 words)

	Earth Floor: Plate Tectonics
		Plates only move a few centimeters each year, so collisions are very slow and last millions of years.
		The edge of the continental plate in the drawing has folded into a huge mountain range, while the edge of the oceanic plate has bent downward and dug deep into the Earth.
		As the edge of the oceanic plate digs into Earth's hot interior, some of the rock in it melts.
	www.cotf.edu /ete/modules/msese/earthsysflr/plates2.html (468 words)

	Earth's Continental Plates - ZoomSchool.com
		At the boundaries of the plates, various deformations occur as the plates interact; they separate from one another (seafloor spreading), collide (forming mountain ranges), slip past one another (subduction zones, in which plates undergo destruction and remelting), and slip laterally.
		Seafloor spreading is the movement of two oceanic plates away from each other (at a divergent plate boundary), which results in the formation of new oceanic crust (from magma that comes from within the Earth's mantle) along a a mid-ocean ridge.
		Plate tectonics from the University of Tennessee (Knoxville).
	www.enchantedlearning.com /subjects/astronomy/planets/earth/Continents.shtml (1171 words)

	[No title]
		These observations proved that new oceanic crust was continually being created at a rate of 1-9 cm/yr and led to the hypothesis of sea-floor spreading.
		Plate tectonics can be used to explain "geologic action" at plate boundaries but falls short in explaining continental scale vertical motions far from plate boundaries.
		Plate Tectonics is consistent with seismic data which show that deep focus earthquakes are associated with subduction zones.
	www.geology.um.maine.edu /ges101/tect.htm (832 words)

	OptIPuter Outreach
		These are zones where two plates move away from each other, allowing magma from the mantle to rise up and solidify as new crust.
		Magmas that form island arcs are produced by the partial melting of the descending plate and/or theoverlying oceanic lithosphere.
		The zone between two plates sliding horizontally past one another is called a transform-fault boundary, or simply a transform boundary.
	education.sdsc.edu /optiputer/teachers/platemovement.html (958 words)

	Tectonic Boundaries (Site not responding. Last check: 2007-09-30)
		Oceanic plates are always subducted under a continental or oceanic plate and this region is known as a subduction zone (Bowler, 1998).
		One distinguishing characteristic of a divergent boundary is an oceanic ridge(the Mid-Atlantic Ridge is the best known example of this) which generally remains in between two conveyor belts of oceanic plate that travel in opposite directions.
		The age of oceanic plates are separated into bands(the width of which indicates the amount of volcanism for that period of time), with equal ages between two corresponding bands separated by the oceanic ridge.
	kjett.bol.ucla.edu /plates6.htm (735 words)

	Plate tectonics: Convergent Plate Boundaries
		The dense, leading edge of the oceanic plate actually pulls the rest of the plate into the flowing asthenosphere and a subduction zone is born!
		Remember that oceanic plates are born at midocean ridges where molten rock rises from the mantle, cools and solidifies.
		When two oceanic plates collide, the plate that is older, therefore colder and denser, is the one that will sink.
	www2.nature.nps.gov /geology/usgsnps/pltec/converge.html (711 words)

	Major Tectonic Plates of the World (Site not responding. Last check: 2007-09-30)
		Where an oceanic plate collides with a continental plate, the oceanic plate tips down and slides beneath the continental plate forming a deep ocean trench (long, narrow, deep basin.) An example of this type of movement, called subduction, occurs at the boundary between the oceanic Nazca Plate and the continental South American Plate.
		Where plates diverge, hot, molten rock rises and cools adding new material to the edges of the oceanic plates.
		Plate tectonics, the branch of science that deals with the process by which rigid plates are moved across hot molten material, has helped to explain much in global-scale geology including the formation of mountains, and the distribution of earthquakes and volcanoes.
	geology.er.usgs.gov /eastern/plates.html (245 words)

	Earth Science resources: Plate tectonics, destructive plate margins
		As the oceanic crust moves down below the continental, rising temperatures and frictional effects cause the oceanic rocks to melt adding to the sub-terranean magma pool.
		The oceanic crust is pushed downwards and forms deep ocean trenches along the plate margin.
		The sub-ducting Nazca plate forms a deep ocean trench running north to south off the coast of Chile whilst the pressure buckling of the American plate has formed the Andes mountain range.
	www.stvincent.ac.uk /Resources/EarthSci/Tectonics/destructive.html (825 words)

	Bryce Canyon National Park: GEODETECTIVE Program (Site not responding. Last check: 2007-09-30)
		Moving plates create and destroy landforms such as mountain ranges, basins, trenches, and deep-sea ridges.
		This melted oceanic crust becomes less dense (because it is now in a liquid form) and therefore rises towards the surface causing continental crust to rise up above it, forming mountains and volcanoes.
		If there is little motion in the "plates", try separating the "plates" from the rest of the wax by cutting simple straight boundaries to separate the "plates" from the excess "crust".
	www.nps.gov /brca/geodet/geodet_crust.html (1264 words)

	Introduction to Plate Tectonics (Site not responding. Last check: 2007-09-30)
		The ways that plates interact depend on their relative motion and whether oceanic or continental crust is at the edge of the lithospheric plate.
		The west margin of the South American continent, where the oceanic Nazca Plate is pushed toward and beneath the continental portion of the South American Plate, is an example of a convergent plate boundary.
		The San Andreas fault in California is an example of a transform plate boundary, where the Pacific Plate slides past the North American Plate.
	volcano.und.nodak.edu /vwdocs/vwlessons/plate_tectonics/part13.html (156 words)

	Plate Tectonics
		Plate tectonics is the all-encompassing theory that allows us to understand the present configuration of the surface of the Earth, to recreate the past positions of the continents and ocean basins, and to make predictions about the future.
		The angle of subduction is related to the age of the plate; the older the subducting plate, the steeper the angle.
		This is primarily a function of equal density of the plates; however, it also occurs due to the direction of movement.
	www.coloradocollege.edu /Dept/GY/rweb/plates.html (1473 words)

	Continental Drift and Tectonic Plates (Site not responding. Last check: 2007-09-30)
		As a result, the oceanic lithospheres generally lie below sea level (for example the entire Pacific Plate, which carries no continent), while the continental ones project above sea level (see isostasy for explanation of this principle, which is essentially a large-scale version of Archimedes' Bath).
		The relative motion of the two plates is therefore either sinistral or dextral.
		The genesis of divergent boundaries is sometimes thought to be associated with the phenomenon known as hotspots.
	www.crystalinks.com /tectonicplates.html (1448 words)

	Activity 1.5 Demonstrating Plate Tectonics with a Box (Grades 4-6) (Site not responding. Last check: 2007-09-30)
		The sheet with the cardboard represents a plate with oceanic and continental crust.
		Note that the sheets are disappearing into the slit similar to oceanic plates at a subduction zone.
		As the sheets (plates) are consumed, the continents move closer together and ultimately collide.
	volcano.und.nodak.edu /vwdocs/vwlessons/activities/p_number5.html (398 words)

	Woods Hole Oceanographic Institution (WHOI) - 2002 Annual Report
		When an ocean plate collides with another oceanic plate or with a plate carrying continents, one plate will bend and slide under the other.
		When an oceanic plate collides with another plate, it slides beneath it in a process called subduction.
		As the subducting plate plunges into the mantle, magma is generated that can erupt at the surface of the overriding plate.
	www.whoi.edu /annualreport02/highlights/subduction.html (375 words)

	[No title]
		Here, the now cold oceanic plate that was generated at an ocean ridge in the distant past is buckled and returned to the mantle.
		As the plate is subducted, it is bent and buckled, causing earthquakes.
		The compressive motion of the converging plates causes the wedge to be deformed and folded as sedimentary and metamorphic rocks onto the coast of the arc.
	www.geosc.psu.edu /Courses/Geosc_001/N017.DOC (2763 words)

	Platetectonics
		Oceanic ridges: where the sea floor is stretched and weakened due to emergence of magma - pushed up to form a ridge
		- the location of the coast to a plate margin (boundary) and the type of margin has an impact on the type of coast.
		- denser oceanic plate descends and the friction causes the lighter continental crust to fold and buckle
	web.bryant.edu /~dlm1/sc366/platetectonics/platetectonics.htm (758 words)

	Study questions for Plate tectonics (Site not responding. Last check: 2007-09-30)
		Therefore, oceanic ridges tend to be very positive features on the seafloor.
		According to plate tectonic theory, a difference in plate ________ results in vastly different rates of _________ for these crustal types, and therefore accounts for this major discrepancy.
		By definition, a passive continental margin is a coastline where there is not an active plate boundary in the vicinity.
	www.mtsu.edu /~cdharris/GEOL100/review-questions/pltec-qs.htm (453 words)

Try your search on: Qwika (all wikis)