* Astronomy

A Canadian scientist says she is involved in an international effort to create 10-year earthquake forecasts for several nations.
Kristy Tiampo of the University of Western Ontario -- the earthquake hazards assessment chairwoman of Canada's Natural Sciences and Engineering Research Council -- says she and colleagues hope to begin producing such 10-year earthquake forecasts within fve years.
The forecasts will be used to suggest to governments which areas should shore up buildings and to determine the order of preparations.

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It's long been known that Vancouver Island is slowly moving eastward toward the mainland. But suddenly, the data showed the movement was reversed.
Eventually, scientists linked this reversal of movement to the tremor events. Right now, Dr. Rogers noted, Vancouver Island is again moving west.
The scientists' findings were presented four years ago at the annual meeting of the American Geophysical Union in San Francisco.
Since then, dozens of scientists from around the globe have begun tracking tremor events.
One day, one of these tremor events will cause the fault line to rupture, he said, resulting in an earthquake magnitude measuring as high as 9.

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A new method of stress analysis in earthquake research has been developed by FOI, the Swedish Defence Research Agency. The method is a breakthrough for better earthquake warnings.
The new method of analysis makes it possible to estimate the complete stress tensor and monitor changes in the magnitude of stress and the instability of faults, which roots the analysis in physics in a manner that earthquake methods normally lack. This makes the method more generally valid, thus facilitating efforts to provide warnings.
Tests with Icelandic micro-tremors from 1990 to 2005 yielded excellent results, with the major earthquakes occurring precisely when they were predicted by the stress analysis. This experience from Iceland therefore indicates that the sites of coming earthquakes can be determined years before they occur.
The Icelandic seismological network where the metering took place started as a Nordic collaborative project in 1988 and has continued as the largest EU project devoted to earthquake warnings. In 2006 the network comprised some 45 metering stations covering most of Iceland. The number of micro-tremors analysed was about 250,000.

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Japanese researchers have discovered a new and sluggish kind of seismic activity that helps reveal the inner workings of faults capable of producing massive earthquakes like the one that generated the 2004 Indian Ocean tsunami.
The so-called "very low frequency" earthquakes join two other types of slow quakes previously detected in the deep portion of subduction zones, where one section of the Earth's crust dives under another. The new kind of seismic activity can itself produce earthquakes of magnitudes 3 to 3.5, but the temblors are too slow to produce shaking felt by humans.

Title: Slow Earthquakes Coincident with Episodic Tremors and Slow Slip Events
Authors: Yoshihiro Ito, Kazushige Obara, Katsuhiko Shiomi, Shutaro Sekine, Hitoshi Hirose

We report on the very-low-frequency earthquakes occurring in the transition zone of the subducting plate interface along the Nankai subduction zone in southwest Japan. Seismic waves generated by very-low-frequency earthquakes with seismic moment magnitudes of 3.1-3.5 predominantly show a long period of approximately 20 s. The seismicity of very-low-frequency earthquakes accompanies and migrates with the activity of deep low-frequency tremors and slow slip events. The coincidence of these three phenomena improves the detection and characterization of slow earthquakes, which are thought to increase the stress on up-dip megathrust earthquake rupture zones.

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