New Technique Provides Earthquake Risk for Major Cities Worldwide

By Larry O’Hanlon

Scientists have developed snapshots of the likelihood of major earthquakes occurring in megacities around the world using a new statistical approach for estimating earthquake risk. The work will be presented today, May 22 at the joint meeting of the Japan Geoscience Union and the American Geophysical Union in Chiba, Japan.

A “nowcast” for Tokyo. The red thermometer at right shows how far along the Tokyo region is in its cycle of smaller quakes between quakes of at least 6.5 magnitude. (John Rundle, UC Davis)

Grant for natural hazards research at UC Davis centrifuge

The National Science Foundation will award almost $5 million over five years to UC Davis to include the large earthquake-simulating centrifuge at the Center for Geotechnical Modeling as part of the new Natural Hazards Engineering Research Infrastructure program.

The geotechnical centrifuge at UC Davis is the largest of its kind in the world. It is used for scale model experiments of the effect of earthquakes on soils and buildings.

The geotechnical centrifuge at UC Davis is the largest of its kind in the world. It is used for scale model experiments on the effect of earthquakes on soils and buildings.

Bio-shock resistant: New center to apply biology to earthquakes, civil engineering

Taking lessons from nature and biology into civil engineering is the goal of the new Center for Bio-inspired and Bio-mediated Geotechnics, including the University of California, Davis, Arizona State University, New Mexico State University and the Georgia Institute of Technology, and funded with a five-year, $18.5 million grant from the National Science Foundation.

The center’s director will be Edward Kavazanjian, a professor of civil engineering and senior scientist at ASU’s Julie Ann Wrigley Global Institute of Sustainability. The UC Davis team will be headed by Jason DeJong, professor of geotechnical engineering in the Department of Civil and Environmental Engineering.

Oaxaca earthquake, one day later

A major earthquake struck Mexico just after 11 a.m. Pacific Time yesterday. Initial reports put the magnitude at 7.9 and relatively close to the surface, which would be a very serious earthquake. However, news reports from Mexico City and then other cities including Oaxaca and Acapulco showed relatively minor damage and few casualties, and the US Geological Survey later downgraded the magnitude to 7.4.

“It’s a good example of the fog of information after an event like this,” said UC Davis geologist Michael Oskin. “It went from 7.9, shallow (10km) and thus a high destructive potential to a 7.4, deep (20 km or deeper, I suspect) and unsurprising event on the subduction interface.”

New approaches to earthquake forecasting

In this interview with Thompson Reuters ScienceWatch, UC Davis interdisciplinary professor John Rundle talks about the new approaches that he and his collaborators have developed to understanding earthquakes over the past 20 years or so. Rather than treating them as elastic rebound movements, Rundle began considering earthquakes as a phase transition — a term physicists use to talk about systems that change abruptly from one state to another.

Rundle and colleagues have now set up a website,, to make earthquake forecasts available to the public.

Retaining walls shaken in test, but not broken

UC Davis civil engineering professor Dawn Cheng recently carried out a series of tests at UC San Diego’s Englekirk Structural Engineering Center. The center has the largest outdoor shake table in the world — meaning that you can build a structure on it then shake it to simulate an earthquake.

Retaining wall on shake tableCheng was carrying out the first tests on retaining walls, used for example to hold back soil from freeways or support bridge abutments across the state. There are thousands of miles of such walls across California, but surprisingly their behavior in earthquakes is not well understood. The tests, which were funded by the California Department of Transportation, will ensure that new retaining walls are designed to high seismic standards.

Virtual Reality demos at AGU

If you are among the 16,000 people attending the American Geophysical Union meeting in San Francisco this week, scientists from the UC VR imageDavis KeckCAVES facility will be running several demonstrations of their interactive virtual reality technology. The demonstrations will be run on a laptop and displayed on a large monitor, so will not have the full immersive, 3-D experience of the KeckCAVES lab itself, but they will use real data in real time and show how scientists can use virtual reality to work with their data.

Earthquake damage photo collection

Geotechnical engineers Ross Boulanger of UC Davis and J. Michael Duncan of Virginia Tech have compiled a comprehensive collection of photos of all kinds of damage the planet can do to our puny human structures, and some of the techniques engineers can use to prevent such damage.

Geotechnical Engineering photo album

Hat tip to, which has collected some of the images in a nice gallery.

NASA turns 50: the UC Davis connections

If you’ve been to the Google home page this morning and clicked through the doodle, you’ll know that the National Aeronautics and Space Administration was established on July 29, 1958. To mark the occasion, here’s a roundup of UC Davis space-related stories.

A View From the New Bay Bridge

The Sacramento Bee’s Ngoc Nguyen took a tour of the new Bay Bridge currently under construction and the Bee has some nice video of the structure on its website. CalTrans is now working on the suspension span of the bridge, which will be the largest self-supported suspension bridge in the world with a 500-foot tower and a single cable anchoring the entire structure. (Print story here.)

Nguyen toured the bridge with a group of civil engineers attending the conference on Geotechnical Earthquake Engineering and Soil Dynamics held in Sacramento this week (the conference also included an equipment show at UC Davis’s Center for Geotechnical Modeling).