Taxonomy term

seismology

Unlocking the Cascadia Subduction Zone's secrets: Peering into recent research and findings

Megathrust earthquake hazards drive much of the research into the 1,000-kilometer-long Cascadia Subduction Zone, which lurks off the coast of California, Oregon, Washington and British Columbia. New studies are helping elucidate what is happening off the Pacific Northwest coast.

20 Jul 2014

Longmenshan fault zone in the spotlight after two major quakes in five years

In May 2008, a magnitude-7.9 earthquake struck near Wenchuan, China, killing more than 80,000 people in the country’s biggest quake since 1950. Then, in April 2013, the magnitude-6.6 Lushan earthquake hit just 90 kilometers to the south — also within China’s Longmenshan Fault Zone, which separates the Tibetan Plateau to the west from the Sichuan Basin to the east — and caused another 200 deaths. Now, scientists have found that a roughly 60-kilometer segment of the fault zone between the epicenters of the two big temblors could be the next to rupture, although no one knows when or how big it might be.

05 Jun 2014

Precise to a fault: How GPS revolutionized seismic research

Conceived in the 1960s to provide precise time and position for the U.S. military, GPS was soon embraced by geodesists and earth scientists. Today, it is an essential tool for geoscience research that extends far below — and above — Earth's surface.

30 Apr 2014

A truly global system

Like the GPS navigation system in your car or smartphone, a high-precision GPS receiver uses signals from satellites to determine the distance from the receiver to the satellite. But that’s where the similarities end. 

30 Apr 2014

Observing a plate boundary

The U.S. Plate Boundary Observatory (PBO), a component of EarthScope, includes more than a thousand continuous GPS stations arrayed across the western United States and Alaska. 

30 Apr 2014

Faking quakes at full scale: Giant shake tables simulate earthquakes to make buildings safer

At a few select facilites around the world, engineers are able to shake full-size buildings to learn how to make them safer during earthquakes. Take a look at the massive shake tables that make it possible.

23 Apr 2014

Giant quake sloshed fjords half a world away

On the morning of March 11, 2011, Leif Hus and his wife Gry Melas Hus were having breakfast in their kitchen overlooking Sognefjord in Leikanger, Norway. It was low tide on a calm and windless day with near-freezing temperatures. As they stood, coffee cups in hand, looking out the window at the fjord, they saw an unusual wave roll in. The wave continued to rise, surging over the seawall into their backyard before receding back into the fjord. Then another wave surged in, and another. As the water rose, engulfing the ladder on their dock, Leif grabbed his cell phone and started filming.

02 Dec 2013

Old photos help scientists relocate 1906 San Francisco quake rupture point

Portola Valley, just south of San Francisco, is famous for its progressive approach to geology. The town was the subject of the first geologic map of California and the first municipality in the state to hire its very own resident geologist. There’s a good reason: The section of the San Andreas Fault that produced the deadly San Francisco quake of 1906 runs right through the town. But where exactly the fault trace lies has long been a mystery. Now, in a new study, researchers have used a combination of new technology and old photographs to relocate the fault line.

25 Nov 2013

World's largest deep earthquake recorded

The seismology world may have a new leader in superlatives: On May 24, 2013, the largest, deep earthquake ever recorded struck beneath the Sea of Okhotsk, between the Kamchatka Peninsula and Russian mainland. Scientists are still puzzling over how such a large event could occur so deep.

30 Oct 2013

Big quakes topple traditional views of fault behavior

If rules are made to be broken, then perhaps conventional wisdom is made to be overturned. The spate of large earthquakes in recent years — the magnitude and location of which have defied scientific expectations in several cases — has provided ample support for these maxims, at least within earth science. For all the confusion, though, data emerging from these events are reshaping and improving our understanding of how faults operate.

14 Apr 2013

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