Understanding mysterious continental intraplate earthquakes

Oct 12, 2007

A new volume published by the Geological Society of America sheds light on mysterious earthquakes in the interiors of continents. These earthquakes, like those that occur in the central U.S., are what the book's editors describe as "an embarrassing stepchild of modern earthquake seismology." Continental Intraplate Earthquakes: Science, Hazard, and Policy Issues provides a comprehensive overview of these rare but very real global hazards.

The plate tectonics revolution of the 20th century elegantly explained why most earthquakes occur where they do – at Earth's plate boundaries. It didn't explain, however, the occurrence of intraplate quakes and the deformation processes that give rise to them. As a result, geologists studying areas like the central U.S., western Europe, and Australia, don't know what causes these quakes, how often they will happen in the future, and how dangerous they are.

"Progress has been slow and somewhat difficult," said volume editor Seth Stein of Northwestern University, Evanston, Illinois, USA. "Because deformation within plates is slow compared to more rapid plate boundary motions, seismicity is much lower and harder to study."

Stein points out that in recent years important insights are emerging with use of new research techniques and approaches. Space geodesy can measure intraplate deformation. Paleoseismology can extend the somewhat sketchy instrumental record backwards in time. Numerical deformation modeling can be used to test hypotheses regarding stresses.

The emerging picture shows earthquakes moving around among faults, which are active for some time and then become inactive for a long time. The results can be used to develop strategies for mitigating earthquake damage while balancing the resources required with those needed for other societal goals.

In organizing the publication Stein and co-editor Stéphane Mazzotti of the Geological Survey of Canada drew on presentations from a number of meetings and other sources that integrated what has been learned from earthquakes around the world. "Because these earthquakes are relatively rare in any given area, combining data from many areas provides valuable insights," said Stein.

One group of papers addresses where intraplate quakes occur and what causes them. A second group assesses the hazards posed and challenges in estimating probability, size, and shaking. A third group explores public policy issues surrounding cost-effective hazard mitigation.

Source: Geological Society of America

Explore further: Cordilleran terrane collage

add to favorites email to friend print save as pdf

Related Stories

Molecular gate that could keep cancer cells locked up

6 hours ago

In a study published today in Genes & Development, Dr Christian Speck from the MRC Clinical Sciences Centre's DNA Replication group, in collaboration with Brookhaven National Laboratory (BNL), New York, ...

Taking great ideas from the lab to the fab

7 hours ago

A "valley of death" is well-known to entrepreneurs—the lull between government funding for research and industry support for prototypes and products. To confront this problem, in 2013 the National Science ...

SR Labs research to expose BadUSB next week in Vegas

7 hours ago

A Berlin-based security research and consulting company will reveal how USB devices can do damage that can conduct two-way malice, from computer to USB or from USB to computer, and can survive traditional ...

Recommended for you

Cordilleran terrane collage

9 hours ago

In the August 2014 issue of Lithosphere, Steve Israel of the Yukon Geological Survey and colleagues provide conclusions regarding the North American Cordillera that they say "are provocative in that they b ...

NASA sees Tropical Storm Halong's 'best side'

11 hours ago

NASA satellite data showed Tropical Storm Halong's "best side" or most powerful side was east of its center. That's where the coldest cloud top temperatures and strongest thunderstorms appeared on satellite ...

User comments : 0