Sentences with phrase «of subduction zone»

Here in Oregon we are the somewhat unwitting hosts of a great deal of methane hydrate research by Oregon State University, some Texas university people (and backing by the good old Houston - based gas industry), of deposits on and near the ocean floor on the Gorda Ridge just off our coast, which is a consequence of the subduction zone geomorphology of the area.

Scientists have been attracted to the region because of the subduction zone located at the bottom of the ocean where the Pacific and North American tectonic plates collide, the Aleutian Trench.

And in April 2014, a Chilean quake ruptured a far shorter portion of a subduction zone than scientists had expected.

The great Sumatra - Andaman earthquake of Dec. 26, 2004, for instance, unzipped a 1,300 kilometer long segment of the subduction zone and unleashed one of history's most destructive, deadly tsunamis.

From the time interval (56 years), the known speed of the Nazca plate, and further knowledge of the subduction zone, the German - Chilean team has calculated the accumulated energy and thus the theoretical slip of the 2016 earthquake to about 3.4 meters.

Intriguingly, the part of the subduction zone that broke was not the part that had built up the most stress, according to a ground - motion study of northern Chile's seismic gap by Marianne Métois, a geophysicist at the National Institute of Geophysics and Volcanology in Rome, and her colleagues (M. Métois et al.Geophys.

The triggering effect was probably accentuated by an offshore «sedimentary wedge» — a mass of sedimentary rock piled up at the edge of the subduction zone boundary offshore from the North Island's east coast.

A new study led by The University of Texas at Austin has found that the occurrence of these big, destructive quakes and associated devastating tsunamis may be linked to compact sediments along large portions of the subduction zone.

U.S. Geological Survey scientist Jeanne Hardebeck calculated the frictional strength of subduction zone faults worldwide, and the stresses they are under.

One of the primary questions they hope to answer is whether the pressures and temperatures experienced at depth here lead to the unusual properties of this subduction zone fault, and if that in turn leads to larger and more powerful earthquakes.

A magnitude - 9.0 earthquake would likely give way along the whole north - south extent of the subduction zone, but it's not well known how far east the shake - producing area would extend, approaching the area beneath major cities such as Seattle and Portland.

«The only way to explain the subsidence of the islands is to have a rupture... in the very deep part of the subduction zone, between 40 and 60 km (25 to 40 miles) depth,» Feuillet said.

What's more, when the minerals return to the surface in the forearcs of subduction zones, they can break down over millions of years, releasing gases back to atmosphere once again.

One way to learn more about the transformations in greater depths of subduction zones is to create similar conditions in the laboratory.

In Japan, the Kuril Islands, and the Solomon Islands, great mega-thrust ruptures have ruptured portions of the subduction zones that were thought too warm or weak to experience earthquakes.

The water also plays a role in the strong earthquakes characteristic of subduction zones.

Not exact matches

An apocalyptically - worded story in the latest issue of the New Yorker detailed the devastation that might result from a high - magnitude earthquake along the Cascadia subduction zone, a fault line that runs from Cape Mendocino, Calif., to Vancouver Island, Canada.

June 17, 2013 — A new subduction zone forming off the coast of Portugal heralds the beginning of a cycle that will see the Atlantic Ocean close as continental Europe moves closer to America.

SASMEX's main focus is on earthquakes originating in the subduction zone off the southern coast of Mexico, where the Cocos tectonic plate subducts below the North American Plate.

The Tehuantepec earthquake originated offshore in the subduction zone, while the Morelos earthquake was an example of in - slab seismicity.

These initial results provide fundamental insights into the behavior of rare, very large earthquakes that may aid in preparation and early warning efforts for future tsunamis following subduction zone earthquakes.

However, the seismic potential of crustal faults within the forearc of the northern Cascadia subduction zone in British Columbia has remained elusive.

To get such a high mountain chain in a subduction zone setting is unusual which adds to the importance of trying to figure out when and how it happened.

They simulated earthquakes with magnitudes between 9.0 and 9.6 originating at different locations along the Aleutian - Alaska subduction zone, a 3,400 - kilometer (2,113 - mile) long ocean trench stretching along the southern coast of Alaska and the Aleutian Islands where the Pacific tectonic plate is slipping under the North American plate.

Combining the 19th - century records of such effects with modern earthquake models helped Beauducel and Feuillet pin down both the quake's magnitude and the location of the fault rupture, the spot where the subduction zone tore apart.

Three basic forces are believed to drive oceanic plate movement: plates are «pushed» away from mid-ocean ridges as new sea floor forms; plates are «pulled» as the oldest parts of the plate dive back into the earth at subduction zones; and convection within the asthenosphere helps ferry the plates along.

«Although our understanding of this margin's structure and development has increased enormously since 2004 due to marine geophysical data collection, as yet very little is known of the properties of the materials that make up this subduction zone,» she continued.

Now scientists are calling attention to a dangerous area on the opposite side of the Ring of Fire, the Cascadia Subduction Zone, a fault that runs parallel to the Pacific coast of North America, from northern California to Vancouver Island.

Therefore developing a better understanding of earthquake and tsunami behavior and potential is a priority for local communities, for the wider Indian Ocean, and for related subduction zones.»

One hint of weak coupling at a subduction zone is the presence of serpentinite — a mineral formed when seawater carried down by a descending plate reacts with mantle rock.

Many of the islands sit above a subduction zone, where two plates meet and one slides haltingly under the other, down into the Earth's mantle.

«Measuring the strength of olivine is critical to understanding how strong tectonic plates are, which, in turn, matters to how plates break and create subduction zones like those along the Cascadia plate, which runs down the west coast of Canada to the west coast of the United States,» said Warren, a geologist in the College of Earth, Ocean, and Environment.

In the early 1980s, two Caltech geophysicists, Tom Heaton and Hiroo Kanamori, compared Cascadia to active quake - prone subduction zones along the coasts of Chile and Alaska and to the Nankai Trough off the coast of Japan.

Exactly the same is true of the Cascadia subduction zone — an almost identical geologic threat off the west coast of North America.

«This ocean drilling expedition will for the first time drill scientific boreholes within the sediments entering this subduction zone, including the layer of sediment that eventually develops into the earthquake - generating fault,» Professor Henstock explained.

Here we are not dealing with large volcanic eruptions of the size of Pinatubo of Mount St. Helens, here we are talking about extreme events: The Toba caldera in the Sumatra subduction zone in Indonesia originated from one of the largest volcanic eruption in recent Earth history, about 74,000 years ago.

On the Pacific Coast, this area sits along the subduction zone known as the Cascadia plate, which runs down the west coast of Canada to the west coast of the United States.

The Earth's lithosphere is divided into several plates that are in constant motion, and today's geologists have a good understanding of what drives these plate movements: heavier ocean plates are submerged beneath lighter continental plates along what are known as subduction zones.

Events of this magnitude normally occur in a subduction zone, where one tectonic plate slides beneath another.

In 1964 a region of this same tectonic clash, called the Alaska — Aleutian Subduction Zone, produced the magnitude 9.2 «Good Friday» earthquake, the second - strongest quake ever recorded.

Schellart's model, which took more than two years to complete on Australia's supercomputer Raijin, has reproduced the evolution of the South American subduction zone, from start to present (initiating some 200 million years ago and thereby the oldest subduction zone in the world), to investigate the origin of the Andes.

The Tohoku - Oki earthquake occurred in a «subduction zone,» a boundary between two tectonic plates where one plate is diving beneath another — in this case, the Pacific plate dives beneath the Eurasian plate just east of Japan.

The focus was on the Nankai Trough, one of three major subduction zones offshore of Japan.

The billion - year time lag between the earliest, «proto - subduction» and the full onset of plate tectonics can be explained by the slow, painstaking development of weak zones within the plates, he proposes.

This subduction has created a collision zone with the potential to generate huge earthquakes and accompanying tsunamis, which happen when faulted rock abruptly shoves the ocean out of its way.

The strain that is released in a subduction zone earthquake is thought to build up in the deep portion of the fault where the two plates are «locked.»

The findings could apply to other faults with similarly thick sediment, such as the Cascadia Subduction Zone in the Pacific Northwest, suggests study coauthor Andre Hüpers, a geophysicist at the University of Bremen in Germany.

«The implication of a confirmed subduction zone is that in addition to the Queen Charlotte Fault, we now have another source which can produce devastating megathrust earthquakes in the area,» said Kao.

Although the rate of subduction varies little along the entire arc, there are complex changes in the geologic processes along the subduction zone that dramatically influence volcanic activity, crustal deformation, earthquake generation and occurrence all along the western edge of South America.

In these regions of «flat - slab» subduction, the Nazca plate moves horizontally for several hundred kilometers before continuing its descent into the mantle, and is shadowed by an extended zone of crustal seismicity in the overlying South America plate.