Two earthquakes struck Ecuador’s coast on Wednesday, leading to one death and light damage in the same region where a magnitude 7.8 tremor killed more than 650 people last month.
Wednesday’s tremors, measuring 6.7 and 6.8 in magnitude, according to the U.S. Geological Survey, cut electricity in some coastal areas and sent people running into the streets as far away as the highland capital of Quito, witnesses said. Continue reading…
Since mid-March, there have been a swarm of earthquakes under Mount St. Helens in Washington State, suggesting that the active stratovolcano is now recharging with magma.
According to the U.S. Geological Survey (USGS), over 130 vertical earthquakes ranging from low magnitudes 0.5 to 1.3 have been detected two to seven kilometres beneath the volcano’s crater. There are about 40 earthquakes at the volcano per week, and the occurrences are increasingly becoming more frequent.
“The magma chamber is likely imparting its own stresses on the crust around and above it, as the system slowly recharges,” reads a release by the USGS. “The stress drives fluids through cracks, producing the small quakes.” Source
Southern California’s section of the San Andreas Fault is “locked, loaded and ready to roll,” a leading earthquake scientist said Wednesday at the National Earthquake Conference in Long Beach.
The San Andreas Fault is one of California’s most dangerous, and is the state’s longest fault. Yet for Southern California, the last big earthquake to strike the southern San Andreas was in 1857, when a magnitude 7.9 earthquake ruptured an astonishing 185 miles between Monterey County and the San Gabriel Mountains near Los Angeles.
CHAPEL HILL, N.C., May 3 (UPI) — The southeastern United States isn’t known for its seismic activity, but the region does experience the odd earthquake.
A new study — published in the Journal of Geophysical Research: Solid Earth — offers an explanation for the phenomenon.
Most earthquakes occur near plate boundaries and major fault lines. The southeastern corner of the United States lies in the middle of the North American Plate, far from the seismically active margins.
However, new analysis suggests the plate’s interior continues to lose bits and pieces of its mantle. As fragments break off and sink toward Earth’s interior, the mantle is left thinner and more brittle — and more susceptible to the fault slipping that triggers earthquakes. Source