Earthquake prediction

Some advancement in Earthquake Prediction - from Nature:

In Japan, small shakes presage big quakes
Clusters of tiny earthquakes that happen every three years could help to signal when the next big one will hit Japan, researchers report in Science.

Small, subtle quakes happen in many places where a slab of sea floor dives beneath a continent, such as in the US Pacific Northwest or off the coast of Chile. But the study of seismic activity in Japan is the first to show that they happen in regular episodes, and that those events can precede larger earthquakes.

If the same patterns hold in other earthquake-prone regions, they could improve seismic risk estimates there, too.

A bit more:

Stress monitoring
Because the 2011 Tohoku earthquake relieved geological stress, Uchida says, that particular section of the fault is not likely to move in a large earthquake any time soon. But by monitoring slow slip to the north and south of Tohoku, seismologists may get a better idea of how much stress is building there and when a large earthquake is likely to strike again. “It means earthquake probabilities should be raised during times of accelerated [slow] slip,” says Gavin Hayes, a seismologist with the US Geological Survey in Golden, Colorado.

Slow slip has happened before other large earthquakes, such as the magnitude-8.1 Iquique earthquake in Chile in 2014. In 2014, off the coast of Guerrero, Mexico, a magnitude-7.2 earthquake occurred about two months after slow slip began, says Mathilde Radiguet, a seismologist at ISTerre Institute of Earth Sciences in Grenoble, France.

And slow slip is common along the Pacific Northwest coast, a spot thought to be ripe for a large earthquake in the zone known as Cascadia. For the past five weeks, in a fairly common occurrence, tiny quakes have been marching south from Vancouver Island and into Washington state. “It is key for us to know as much as possible about unsteady slow slip in Cascadia,” says Heidi Houston, a seismologist at the University of Washington in Seattle.

More on the Cascadian Episodic Tremor and Slip Events at the Pacific Northwest Seismic Network - new entries are at the bottom of the page.