seismology

When the magnitude 9.0 Tōhoku earthquake struck off the coast of Japan in 2011, its seismic shivers did more than ripple through the planet. At least one wave traveled 2,900 kilometers (1,800 miles) down to the boundary between Earth’s mantle and liquid outer core, where it was reflected right back to the surface. And there, […]

The Jiao-Liao-Ji belt is one of three major Paleoproterozoic orogenic belts within the North China Craton, yet its tectonic evolution remains controversial. To address this, we investigated the crustal structure using receiver function analysis of 38 broadband seismic stations from profile NCISP-10, which traverses the Liaodong region in the northeastern North China Craton. Our results reveal tha…

An extremely unusual tectonic movement took place 15 minutes after the Tohoku earthquake in 2011, causing almost the whole of Japan to move 5 millimetres to the east

An extremely unusual tectonic movement took place 15 minutes after the Tohoku earthquake in 2011, causing almost the whole of Japan to move 5 millimetres to the east

This “extraordinary” event was likely caused by seismic waves bouncing off Earth’s core, researchers found

When the magnitude 9.0 Tōhoku earthquake struck off the coast of Japan in 2011, its...

The wave's round trip to Earth's core set off a fault slip along Japan's plate boundaries, revealing a seismic hazard scientists hadn't recognized.

A new study suggests Southern California's major fault system is more stressed than at any point in the last 1,000 years. Researchers found that the Cajon Pass, where the San Andreas and San Jacinto faults meet, could act as an “earthquake gate” that determines whether a future rupture spreads across both faults. Current conditions resemble those that preceded some of the region’s largest histori…

If a movie opened with scientists discovering hundreds of earthquakes deep under Antarctica – in...

It's called California's Big One for a reason. For more than a century, tectonic pressure...

Can fault mechanics and friction laws reproduce the full spectrum of observed seismicity?

Tectonic stress has reached peak levels in key areas near Los Angeles. PNSN Director Harold Tobin is interviewed.

Map of the Aleutian Arc in Alaska and the Andreanof study area. The lower map shows where ocean-bottom seismometers and land seismic stations recorded sound waves from an active-source seismic experiment conducted aboard the R/V Marcus G. Langseth , allowing the authors to image the deep structure of the arc crust beneath several Aleutian volcanoes. The black lines show the Langseth ship track an…

The well-known seismologist on the need for the U.S. to recalibrate its social commitment to science

As the world arrives in Seattle for five weeks of thrilling World Cup matches, the Pacific Northwest Seismic Network will be using the same seismometers that provide early warning for earthquakes to track the excitement and energy of the crowds.

Antarctica was long thought to be seismically calm, but new technology makes it possible to detect unexpected types of earthquakes beneath the ice.

Scientists have discovered that a major earthquake zone in Southern California may be carrying more built-up stress than at any time in the past 1,000 years. While this does not mean a large earthquake is about to happen, researchers say the findings highlight the importance of being prepared. Earthquakes occur when stress builds up along […] The post California’s “earthquake gate” may be under m…

7.8-magnitude quake hit the southern island of Mindanao killing at least 55 people and leaving a trail of destruction It was just before midnight when the rescue team pulled the body from the rubble of a grocery store destroyed by the most powerful quake to hit the Philippines in half a century. The family wailed at the sight. “While tragic, it offered the family a painful consolation,” said Rene…

The largest Philippines shock in a half century -- a magnitude 7.8 event -- struck an earthquake-weary country on June 7, 2026, shaking the southernmost island of Mindanao. As of this writing, the Philippines authorities are reporting 47 deaths, several building collapses, and extensive building and infrastructure damage in General Santos City, which lays 55 kilometers (35 miles) north of the ep…

Scientists have confirmed a rare “impossible” earthquake deep beneath Utah, revealing a hidden source of seismic activity inside Earth’s mantle. Nearly five decades after a puzzling earthquake struck deep beneath northern Utah, scientists have confirmed that the event was real and part of a rare category of earthquakes that occur much deeper underground than researchers [...]