subduction zone, large-scaled narrow region in the earth's crust where, according to plate tectonics plate tectonics, theory that unifies many of the features and characteristics of continental drift and seafloor spreading into a coherent model and has revolutionized geologists' understanding of continents, ocean basins, mountains, and earth history.
..... Click the link for more information. , masses of the spreading oceanic lithosphere bend downward into the earth along the leading edges of converging lithospheric plates where it slowly melts at about 400 mi (640 km) deep and becomes reabsorbed. Subduction zones are usually marked by deep ocean trenches that often exceed 6 mi (10 km) compared to the ocean's overall depth of 2 to 4 mi (3 to 5 km). A pattern of earthquakes of shallow, intermediate, and deep focus occurs along the same angle as the descending plate, which is steeply inclined (30°–60°) toward the continent behind the trench in a zone called the Benioff Zone, discovered by the U.S. seismologist Hugo Benioff. This earthquake pattern enables geophysicists to trace the descending plate to depths of 600 to 700 km (370–440 mi), where temperatures are thought to be between 1,000°C; and 2,000°C; (1,800°–3,600°F;). As the oceanic plate descends, friction between the two plates probably causes partial melting of the descending plate forming a magma of andesitic composition that rises along fractures. If the overlying crustal plate is oceanic, the magma may erupt to form volcanic island arcs, such as Japan or the Aleutians. If the overlying plate is continental, a line of batholiths and volcanoes may be created as in the Coast Ranges of Canada and the W United States. See continent continent, largest unit of landmasses on the earth. The continents include Eurasia (conventionally regarded as two continents, Europe and Asia), Africa, North America, South America, Australia, and Antarctica.
..... Click the link for more information. ; continental drift continental drift, geological theory that the relative positions of the continents on the earth's surface have changed considerably through geologic time. Though first proposed by American geologist Frank Bursley Taylor in a lecture in 1908, the first detailed theory
..... Click the link for more information. ; seafloor spreading seafloor spreading, theory of lithospheric evolution that holds that the ocean floors are spreading outward from vast underwater ridges. First proposed in the early 1960s by the American geologist Harry H.
..... Click the link for more information. .

subduction zone

Oceanic trench area in which, according to the theory of plate tectonics, the seafloor underthrusts an adjacent plate, dragging the accumulated trench sediments downward into the Earth's upper mantle. See also deep-sea trench.

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No references found	Was the larger subduction zone shaking off stress from the two giant plates locked against each other? Scientists find fault off coast by The Register-Guard (Eugene, OR) The culprit is the Cascadia subduction zone, which geologists say is a near twin of the fault zone that produced the deadly Indian Ocean earthquake and tsunami in late 2004. First tsunami-resistant shelter in US planned by residents of small ... by Asian News International Topics include Precambrian tectonics and the supercontinent cycle, implications of plate tectonics for environmental change, large igneous provinces, rifted continental margins, ocean ridges, continental transforms, subduction zones, and many organic examples. Global tectonics, 3d ed by SciTech Book News	subcritical flow subcritical mass subcritical reactor subcrop subcrust subcutaneous subcutaneous connective tissue subcutaneous emphysema Subcutaneous Musculature subcutaneous mycosis subcycle generator subdevice bit subdiagonal subdirectory subdivided capacitor subdivided truss subdivision subdivision graph subdivision regulations subdomain Subdominant subdrain subdrainage subdrilling subduction subduction zone subduction zones subdural hematoma subdural hemorrhage Subdwarf subdwarf star subdwarf symbiotic subendothelial layer Subensign Subequatorial Belt suberic acid Suberin suberinite Suberization suberose subfactorial Subfamily subfeeder subfeldspathic subfield subfloor subflooring subfolder subframe subgelisol Subgenus	subduable Subdual Subdual Subduce Subduce subducere subduct subduct subduct subduct subductal subductal subductal Subducted Subducted Subducted Subducting Subducting Subducting Subducting boundary Subducting boundary Subducting boundary subduction subduction subduction subduction subduction Subduction boundary Subduction boundary Subduction boundary subduction zone Subduction zones Subduction zones Subduction zones subducts subducts subducts subdue subdue subdued subdued subduedness Subduement subduer subduer subduers subduers subdues subdues subduing subduing Subdulcid Subduple Subduple ratio Subduplicate Subduplicate ratio subdural subdural subdural abscess subdural abscess Subdural bleeding

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Was the larger subduction zone shaking off stress from the two giant plates locked against each other?

Scientists find fault off coast by The Register-Guard (Eugene, OR)

The culprit is the Cascadia subduction zone, which geologists say is a near twin of the fault zone that produced the deadly Indian Ocean earthquake and tsunami in late 2004.

First tsunami-resistant shelter in US planned by residents of small ... by Asian News International

Topics include Precambrian tectonics and the supercontinent cycle, implications of plate tectonics for environmental change, large igneous provinces, rifted continental margins, ocean ridges, continental transforms, subduction zones, and many organic examples.

Global tectonics, 3d ed by SciTech Book News