all earthquakes stories

Global warming yields 'glacial earthquakes' in polar areas

70652986 — Mon, 26 Mar 2007 06:25:43 -0400

Seismologists at Harvard University and Columbia University have found an unexpected offshoot of global warming: "glacial earthquakes" in which Manhattan-sized glaciers lurch unexpectedly, yielding temblors up to magnitude 5.1 on the moment-magnitude scale, which is similar to the Richter scale. Glacial earthquakes in Greenland, the researchers found, are most common in July and August, and have more than doubled in number since 2002.

Scientists Göran Ekström and Victor C. Tsai at Harvard and Meredith Nettles at Columbia reported on Greenland's glacial earthquakes in the journal Science. Ekström, Nettles, and colleagues first described glacial earthquakes in 2003, but that report did not recognize the seasonality or growing frequency of the phenomenon.

KSG prof starts earthquake relief Web site

70652986 — Mon, 26 Mar 2007 05:41:18 -0400

Assistant Professor of Public Policy Asim Khwaja, with collaborators Jishnu Das and Tara Vishwanath from the World Bank and Tahir Andrabi from Pomona College, has rushed to create a Web site that can help coordinate relief efforts for the Pakistan earthquake. The site, complete with a list of affected villages and satellite maps, aims to ensure that places off of main roads and in other less accessible locations aren't forgotten.

New earthquake mapping system could save lives

70652986 — Mon, 26 Mar 2007 05:20:21 -0400

"The earthquake-hazard maps currently in use are based on the premise that the closer a building is to a large fault, the better designed it should be," says Harvard earthquake expert John Shaw. "But what these new, comprehensive 3-D models we've developed tell us is that this basic rule of proximity doesn't always work." A case in point is the quake that interrupted the 1989 World Series in San Francisco.

Earthquake data is less shaky

70652986 — Mon, 26 Mar 2007 05:20:24 -0400

Pinpointing the epicenter of an earthquake is not easy. Conventional one-dimensional seismic-velocity models often fall short of the mark, particularly in terms of depth, mislocating seismic events by an average of about seven kilometers. In a three-year study funded in part by the American military's Defense Threat Reduction Agency, Harvard researcher Michael Antolik has developed a new simulation model that consistently positions seismic events with greater precision, reducing the mislocation to only six kilometers on average. One kilometer's difference might not seem like much, but it could help prevent an international incident. Antolik's research is primarily devoted to successful monitoring of the Comprehensive Nuclear Test Ban Treaty endorsed by the United Nations in 1996.

Discovering a new earthquake fault under Los Angeles

70652986 — Mon, 26 Mar 2007 05:04:56 -0400

"Los Angeles is caught in a vise," says John Shaw, an associate professor of structural and economic geology at Harvard who was half of a research team that discovered a large, active crack in the earth, capable of causing destructive earthquakes, under Los Angeles. The researchers announced their discovery in March 1999. The crack, or fault, does not break the Earth's surface, so it remained hidden until Shaw and a colleague from the University of California, San Diego, found it in 1998. Los Angeles "is locked between converging sections, or plates, of Earth's crust, carrying North America and part of the Pacific Ocean floor.