Category: Publications

by Jennifer Schmidt, Ph.D. (@DrJenGEO) Researchers used seismic signals from 8,000 earthquakes after the Gorkha quake in 2015 to image the fault structure beneath Nepal. They found a system of …

As of today, some 24 people are dead and 650 injured, and many more are unaccounted for in collapsed concrete buildings on the coastal plains surrounding the epicenter. The quake likely struck on a ‘blind thrust fault’ that does not reach the Earth’s surface but had nevertheless been previously identified by geologists.

Realtime aftershock statistics may be able to identify whether an even larger event is likely to follow, the authors of a new study argue. Additional prospective testing and more strategic public communication will be needed prior to deployment

Warnings were issued for the magnitude-4.5 and magnitude-4.7 quakes 5-6 seconds after they ruptured via ShakeAlert, and alerts reached beta testers of the MyShake app about 2 seconds later. While important progress, these intrinsic delays mean that those who experienced strong shaking received no warning. Alert delays may be longer as the number of alert recipients grows.

The recent acquittal of the TEPCO executives in the Fukushima power plant tragedy hearkens back to the trial of the Italian seismologists who were charged with negligence after the L’Aquila, Italy, earthquakes. Both events raise the question: How much do you prepare for the most dreadful disasters, which result from truly large or rare paroxysms of the Earth?

A 2018 study published in Nature by Phoebe DeVries and her colleagues at Harvard and Google claimed that Deep Learning was able to predict the locations of aftershocks with accuracies far greater than Coulomb stress transfer could achieve

Tiegan Hobbs, Ph.D., Postdoctoral Seismic Risk Scientist, Temblor @THobbsGeo Across the planet, people dropped under their tables at 10:17am on 10/17 to practice what to do in the event of …

17 Oct 2019 marks the 30th anniversary of the Loma Prieta earthquake, the Bay Area “wake-up call” that revealed our weaknesses and catalyzed our preparation. But the quake has been …

Another earthquake with magnitude greater than 4 has struck California in less than a day. It occurred on a portion of the San Andreas Fault which is relatively quiet, but …

Last night, nearly everyone in the greater Bay area was awakened at 10:30 pm by a Magnitude 4.5 shock near the town of Pleasant Hill, north of Walnut Creek

A new comprehensive study of almost 100,000 earthquakes in Japan suggest that large or small, quakes look alike in the first 0.2 seconds

One hospital, four schools, and nine administrative buildings are severely damaged. Some 29 schools of various degrees of damage were forced to close, at least temporarily.

Based on the M 5.7 aftershocks thus far, there is a 3% chance that it could trigger a magnitude-6.5 or larger shock in the next year. The M 5.7 also brought a portion of the Marmara Fault significantly closer to failure.

A fault lying just a few kilometers below Los Angeles is active, according to new research. The work suggests previous examinations of so-called blind-thrust faults might need to be revisited …

Just two days shy of the one-year anniversary of the deadly earthquake and tsunami in Palu, Indonesia, a major earthquake ruptured beneath the nearby island of Maluku on the morning of Thursday, September 26. Local agencies are reporting 20 dead and 2,000 displaced in the wake of this M 6.5 earthquake.

The Magnitude 7.1 earthquake abruptly halted aftershocks on the M 6.4 cross fault. It also produced a far-flung aftershock sequence that touched the San Andreas, but refused to cross the Garlock Fault.

Tiegan Hobbs, Ph.D., Postdoctoral Seismic Risk Scientist, Temblor (@THobbsGeo) Sandwiched in the neighborhood of the 1960 M=9.5, 2010 M=8.8, 2015 M=8.3 and 1985 M=7.8 earthquakes, a M=6.8 earthquake went virtually unreported …

Engineers may have found a way to measure displacement between floors of multistory buildings cheaply, accurately and in real-time, paving the way for quick analysis of the stability of critical infrastructure (e.g. hospitals, airports, water treatment plants) in the event of an earthquake.

A new image of the ground deformation, a rich and enigmatic foreshock sequence, aftershock trends we can explain, and others that are more elusive. This is also the time see how Temblor app’s hazard forecast for Ridgecrest fared.

The 50-km-long rupture has triggered widely dispersed aftershocks. However, almost none of these struck on the faults that the M 7.1 brought closer to failure: The major Garlock Fault; or the Blackwater, Panamint Valley, or Sierra Nevada Faults.

Ross S. Stein, Ph.D., Tiegan Hobbs, Ph.D., Chris Rollins, Ph.D., Geoffrey Ely, Ph.D., Volkan Sevilgen, M.Sc., and Shinji Toda, Ph.D.   The M 6.4 earthquake loaded the site where the …

While it wasn’t the ‘Big One’, activity near the Revere-Dellwood Fault at the northern end of the Cascadia Subduction Zone is a reminder to Canadians to be prepared for shaking. 

Tiegan Hobbs, Ph.D., Postdoctoral Seismic Risk Scientist, Temblor (@THobbsGeo) Chris Rollins, Ph.D., Postdoctoral Researcher, Michigan State University   Citation: Hobbs, T.E. and Rollins, C., (2019), Earthquake early warning system challenged …

The site of the 4th of July shock was stressed by the great 1872 Owens Valley quake and the 1992 Landers quake. Their overlapping stress lobes may have raised the stakes for this region.

On June 23, a Mw=3.6 earthquake struck Colonna, Italy, southeast of Rome. Despite initial fears that it was yet another large quake near the central Apennines, it struck instead nearby the Alban Hills volcanic complex and the source of the famed Tivoli marble.

While Japan is moving entire towns out of the tsunami zone in the wake of the 2011 Tohoku disaster, Oregon is doing the opposite, trading public safety for developer profits.

Mars InSight Lander: Marsquakes, Breakthroughs, and Breakdowns

Could the 2019 M=6.4 Yamagata-Oki, Japan, earthquake be an aftershock of an M=7.5 event that struck in 1964

Previous research suggests that not until halfway through the rupture—90 seconds for an M=9 shock—can one predict its magnitude, but new findings could bring this down to 10-15 sec, which would greatly extend and enhance Earthquake Early Warnings.

The mysterious ‘Fontana Trend’ lit up in shallow and widely felt shocks during the past week, putting residents on edge. The swarm lies near the junction of the major Sierra Madre and San Jacinto Faults.

We welcome inquiries from scientists and institutions for such an ambitious yet discounted project. Resources from ICDP, national funding agencies, and potentially other foundations could be leveraged to take advantage of this unique tectonic and temporal opportunity.

Debido a su ubicación costa afuera y una profundidad moderada, el temblor del jueves provocó pocos daños. Pero varios indicios sugieren que la suerte de El Salvador no durará por mucho más. Este evento también resalta el creciente número de terremotos extensionales grandes: una tendencia global con implicaciones de peligro importantes.

Because of its offshore location and moderate depth, Thursday’s shock did little damage. But many indications suggest that El Salvador will not stay so lucky for long. This event also highlights the increasing number of large extensional earthquakes: a global trend with important hazard implications.

A magnitude-8.0 quake shook deep below the Amazon Rainforest in Peru, causing extensive liquefaction and shaking from Colombia to Chile.

A magnitude-7.5 quake broke the same fault that produced a magnitude-8.0 quake in 2000, an extraordinarily short recurrence time that also broke all our rules

An open invitation for researchers to use these remarkable Costa Rica quakes as a collaboration laboratory

Two deadly and damaging quakes late last month were probably unrelated to each other.

The authors claim they found dynamic triggering of tiny aftershocks up to 275 km (150 mi)
from an M=7.2 mainshock in 2010, but they have not proved their case.

While exact repeats of earthquakes are rare, if the 1906 quake did strike again, what will be our excuse for being so unprepared?

In one case, the fault rupture and its associated seismicity had been shifted toward a volcano in support of the author’s hypothesis; in the other, seismograms from temporary near-fault stations had been manufactured. In both cases, evaluation committees and universities called for retractions.

The magnitude 7.1 earthquake, which struck Mexico City on 19 September 2017, caused devastation in the city and its surroundings. 369 people died, 57 buildings collapsed, and a much larger number was seriously damaged.

A new model joins two others in confirming the hazard posed by the tectonic forces that are squeezing and shearing greater LA.

India is one of the countries with the most earthquake-related deaths. Just in the past century, over 100.000 people have died due to earthquakes in the country (Bilham, 2009)

The megathrust fault lacks large subduction zone earthquakes in this region. What do these extensional earthquakes tell us?

The earthquake is surrounded by recent great quakes; whether one could strike here is uncertain

The Coquimbo region has an unusual, increasing seismicity that may be preparing the area for a very large earthquake – Prof. Raul Madariaga

One may think that these quakes are small, so why do they matter? Why should I care?

The partial shutdown could make things worse

Japanese authorities declared the Jan 3 shock to be an independent event; we argue that it was a product of the 2016 quake, which profoundly changed the hazard.

It’s been over four months since we wrote about the powerful Kumamoto quake sequence: The 15 April 2016 Mw=6.2 (Mjma 6.5) Kumamoto, Japan, shock, which was succeeded 28 hours later by the very damaging Mw=7.0 (Mjma 7.3) shock on the same fault system. We can now give you a preview of crucial new discoveries by Japanese and other researchers.

Could this happen again now? As with precursory swarms, progressive earthquake sequences are uncommon.

Was the M=6.1 a foreshock of the M=7.0, or was the M=7.0 an aftershock of the M=6.1?