Tag Archives: subduction zone

‘Slow Slip’ Earthquakes’ Hidden Mechanics Revealed

AUSTIN,
Texas — Slow slip earthquakes, a type of slow motion tremor, have
been detected at many of the world’s earthquake hotspots, including
those found around the Pacific Ring of Fire, but it is unclear how
they are connected to the damaging quakes that occur there.
Scientists at The University of Texas at Austin have now revealed the
earthquakes’ inner workings using seismic CT scans and
supercomputers to examine a region off the coast of New Zealand known
to produce them.
(more…)

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Clam Fields Found at Deep, Low-Temperature Mariana Vents

Scientists have marveled at the unusual life forms thriving at high temperature hydrothermal vents of the deep ocean.

Now the discovery of clam communities near lower temperature vents in the Mariana Trench is providing information about both the biogeography of the clams and the extent of the serpentinite vents that sustain them. (more…)

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Stiff Sediments Made 2004 Sumatra Earthquake Deadliest in History

AUSTIN, Texas — An international team of geoscientists has discovered an unusual geological formation that helps explain how an undersea earthquake off the coast of Sumatra in December 2004 spawned the deadliest tsunami in recorded history.

Instead of the usual weak, loose sediments typically found above the type of geologic fault that caused the earthquake, the team found a thick plateau of hard, compacted sediments. Once the fault snapped, the rupture was able to spread from tens of kilometers below the seafloor to just a few kilometers below the seafloor, much farther than weak sediments would have permitted. The extra distance allowed it to move a larger column of seawater above it, unleashing much larger tsunami waves. (more…)

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WHOI Experts Stress Lessons From Japan Earthquake

While Japan’s 8.9-magnitude earthquake and accompanying tsunami represent a devastating natural disaster for the country’s residents, scientists should also seize upon the massive temblor as an important learning tool for future quakes around the world, including the Pacific Northwest coast of the United States, according to experts from the Woods Hole Oceanographic Institution (WHOI).

WHOI geophysicist Jeff McGuire said such lessons may be particularly germane to residents of Northern California, Oregon, Washington and Vancouver–a region he said, could be subject to a similar quake/tsunami scenario. “Today’s earthquake happened on a subduction zone thrust fault where the Pacific plate subducts, or dives, under the Japanese islands,” he said. “Japan regularly has large earthquakes and tsunamis all along its east coast due to subduction. (more…)

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