Futurity.org » seismology

Can computers predict the next tsunami?

Dan Stober-Stanford — Thu, 15 Dec 2011 19:16:19 +0000

STANFORD (US) — Scientists have developed computational models of the earthquake and resulting tsunami that devastated Japan in 2010 in order to predict disasters of the same scale.

When the magnitude 9.0 earthquake struck off the coast of Japan in March, it triggered a tsunami that killed more than 20,000 people and destroyed entire cities. It was the largest earthquake ever recorded in Japan, and the scale of the disaster stunned even geophysicists who specialize in earthquake science.

Earthquakes: Mega-heat, miniscule space

Richard Lewis-Brown — Tue, 18 Oct 2011 14:05:28 +0000

BROWN U. (US) — In an earthquake, rock surfaces sliding past each other create intense stress and heat—but only in super-small places where the surfaces actually touch.

This intense heating can occur even while the temperature of the rest of the fault remains largely unaffected, a phenomenon called flash heating.

New view of California’s tectonic plates

Richard Lewis-Brown — Tue, 11 Oct 2011 16:09:31 +0000

BROWN (US) — The highest resolution picture ever obtained of southern California’s lithosphere shows its thickness differs markedly, offering new insight into how rifting shaped the area’s terrain.

Rifting is one of the fundamental geological forces shaping the planet, but because it involves areas deep below the Earth’s surface, scientists have been unable to understand fully how it occurs. What is known is that with rifting, the center of the action lies in the lithosphere, which makes up the tectonic plates—including the crust and part of the upper mantle.

Teams compete to forecast quakes

Andy Fell-UC Davis — Wed, 05 Oct 2011 14:08:46 +0000

UC DAVIS (US) — The best earthquake forecasts are about 10 times more accurate than a random prediction, according to new research.

For the study published in the Proceedings of the National Academy of Sciences, researchers from the University of California, Davis compared seven different earthquake forecasts (including their own) that were submitted to a competition organized by the Southern California Earthquake Center.

Be warned: Seismologists on trial in Italy

Louis Bergeron-Stanford — Sun, 02 Oct 2011 18:28:53 +0000

STANFORD (US) — The manslaughter trial of six Italian seismologists highlights the need for scientists to put more effort into explaining their work to the public, says geophysicist Greg Beroza.

He calls for seismologists to issue “earthquake forecasts” on an ongoing basis to help the public understand changes in the likelihood of a major earthquake occurring in a given region.

Japan’s tsunami picked up by radar

Andy Fell-UC Davis — Mon, 29 Aug 2011 15:54:12 +0000

UC DAVIS (US) — The tsunami that devastated Japan on March 11 was the first to be observed by high-frequency radar, raising the possibility of new early warning systems.

“It could be really useful in areas such as southeast Asia where there are huge areas of shallow continental shelf,” reports John Largier, an oceanographer at the University of California, Davis and author of a new paper published in the journal Remote Sensing.

Mexico quake’s path veered from norm

Deborah Williams-Hedges-Caltech — Mon, 15 Aug 2011 15:06:48 +0000

CALTECH (US) — The El Mayor-Cucapah earthquake that struck Baja California in April 2010 took a divergent route, causing a fault line that remained straight on the surface but was warped and complicated at depth.

In a typical earthquake, the line of intersection between the area where the fault slips and the ground is more complicated at the surface than it is below. Transform plate boundary structures—where two plates slide past one another—tend to be vertically oriented, which allows for lateral side-by-side shear fault motion.

Japan earthquake rocked soil stability

John Toon-Georgia Tech — Tue, 26 Jul 2011 17:31:57 +0000

GEORGIA TECH (US) — Japan’s March 11 magnitude 9.0 earthquake weakened the subsurface rock and soil by as much as 70 percent, according to a new study.

Understanding how subsurface materials respond could be vital information for engineers and architects designing future buildings that are able to withstand the level of acceleration measured in the Japan quake.

Stiff sediment caused killer tsunami

Tim Green-U. Texas — Fri, 24 Jun 2011 15:59:59 +0000

U. TEXAS-AUSTIN (US)/U. SOUTHAMPTON (UK) — A thick plateau of hard, compacted sediment was a major factor in the 2004 undersea earthquake off the coast of Sumatra that spawned the deadliest tsunami in recorded history.

Once the fault snapped, the rupture was able to spread up from tens of kilometers below the seafloor to just a few kilometers below the seafloor, much farther than weak sediments would have permitted—allowing it to move a greater column of seawater above it, unleashing much larger tsunami waves.

Tokyo faces risk of massive aftershock

Andy Fell-UC Davis — Fri, 18 Mar 2011 20:23:31 +0000

UC DAVIS (US) — Computer models suggest Tokyo may be at serious risk from a massive aftershock and associated tsunami, according to seismologist John Rundle.

The March 11 magnitude 9.0 temblor near Sendai, Japan, has been followed by hundreds of powerful aftershocks that have migrated southwards, notes Rundle, who is professor of geology and physics at the University of California, Davis.