Free Newsletters - Space - Defense - Environment - Energy - Solar - Nuclear
by Staff Writers
Karlsruhe, Germany (UPI) Jul 5, 2012
A recently discovered form of deep seismic activity may provide clues about destructive earthquakes that occur at shallower depths, European researchers say.
Tectonic tremor is a new type of seismic signal that seismologists started studying only within the last few years. It is less hazardous than earthquakes and occurs at greater depths.
Tectonic tremors cause relatively weak ground shaking, and while they may last longer than earthquakes, they do not represent any direct danger, researchers said.
"Both earthquakes and tremor have the same cause. They result from the relative movement on fault surfaces, a result of the motion of the tectonic plates," seismologist Rebecca Harrington of the Karlsruhe Institute of Technology in Germany said.
"While earthquakes at our research site in California typically occur at depths of up to 15 kilometers (10 miles) below the surface, tectonic tremor signals are generated at depths ranging from approximately 15 to 35 kilometers (10 to 18 miles)," she said.
Tectonic tremor signals have a unique character that differs from earthquakes, making them more difficult to detect, researchers said.
Researchers have recorded 2,600 tremor events that are being studied in detail.
"We understand very little about what happens on a fault when it ruptures," Harrington said. "The tectonic tremor generated on the deep part of a fault may provide clues about the behavior on the more shallow parts of a fault where more damaging earthquakes occur."
Tectonic Science and News
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement|