Sunday, March 30, 2014

Earthquakes In The News








A 4.8 magnitude quake rocked Yellowstone National Park in Wyoming near the border with Montana, the US Geological Survey said. There were several aftershocks with a magnitude over 3.
The earthquake occurred 37 kilometers northeast of West Yellowstone, Montana at 6:34 am local time (1234 GMT) Sunday.
The quake was centered almost in the middle of Yellowstone National Park, near the Norris Geyser Basin, said Peter Cervelli, a spokesman for the USGS Yellowstone Volcano Observatory, NBC News reported.
He added that any damage from the temblor would likely be minor, noting there are not many visitors in the park at the moment.
There were no immediate reports of damage.
According to USGS there were four aftershocks recorded with a magnitude from 3.1 to 3.3. The USGS said that more are expected.
The secondary shockwaves are usually less violent than the main quake but can be strong enough to do additional damage to weakened structures, the USGS said.
Cervalli stated that the quake is not expected to trigger any volcanic activity. 

Yellowstone National park, North America's largest volcanic field, is the home to a caldera, sometimes referred to as the Yellowstone Supervolcano. Due to the volcanic and tectonic nature of the region, the caldera experiences 1 to 20 earthquakes every day, according to Yellowstone observatory. However they are very weak often measuring much less than magnitude 3. 


The quake on Sunday was the most powerful to hit the park since 1985. In the fall of 1985 in the northwest rim of the caldera during a three-month period of increased earthquake activity over 3000 events of magnitude 0 to 4.9 were recorded by seismologists. 


"Our best evidence is that the crustal magma chamber is filling with molten rock," said seismologist Robert B. Smith, lead author of the study and professor of geophysics at the University of Utah.

"But we have no idea how long this process goes on before there either is an eruption or the inflow of molten rock stops and the caldera deflates again," he added.











A number of smaller aftershock earthquakes have been hitting the Los Angeles, California area over the past 24 hours following the 5.1 magnitude earthquake that struck on Friday night.

The recent activity has put locals on edge and caused significant destruction to some of the region's water mains, as well as some structural damage to buildings and apartments.
The 5.1 quake's epicenter was in Orange County, one mile east of La Habra and four miles north of Fullerton, the U.S. Geological Survey has confirmed. Shortly after that larger earthquake nearly two dozen more aftershocks followed.
The, a magnitude-4.1 shake hit the area on Saturday afternoon, and that tremor was centered about a mile and a quarter southeast of the Los Angeles County community of Rowland Heights, the geological agency reported.
Los Angeles Mayor Eric Garcetti said, "Tonight's earthquake is the second in two weeks, and reminds us to be prepared."
The recent earthquakes comes just shortly after a 4.4 magnitude earthquake hit Los Angeles near the downtown area about a week ago. That earthquake also did not cause significant damage but shook buildings and was felt across the area.








The primary swarm of earthquakes has been centered in northwestern Logan County and northeastern Kingfisher County, about 12 miles north of Crescent, or about 46 miles north of Oklahoma City.
In that cluster, the USGS has recorded 11 earthquakes ranging in magnitude from 2.6 to 4.4 between 10 p.m. CDT Saturday and 7 a.m. Sunday.
A magnitude-4.4 jolt at 9:09 a.m. CDT Sunday became the state's strongest earthquake so far in 2014. Earlier in the swarm, two earthquakes measuring 4.3 on the moment magnitude scale had been the strongest earthquakes so far in 2014 in Oklahoma, eclipsing a 4.1 jolt centered near Langston on Feb. 8.
Those magnitude-4.3 tremors, which occurred at 1:51 a.m. and 3:42 a.m. CDT Sunday respectively, were both felt across a wide area. The "Did You Feel It?" section of the USGS website received reports of shaking as far north as the Kansas City metropolitan area and as far south as Norman, Okla., from both earthquakes. Vibrations were also felt as far east as the Tulsa area from both incidents.
A separate cluster of earthquakes occurred near Choctaw, an eastern suburb of Oklahoma City, on Saturday and Saturday night. Six earthquakes ranging in magnitude from 2.4 to 3.7 were reported between 1 a.m. CDT Saturday and 1 a.m. CDT Sunday. The strongest temblor occurred at 10:08 p.m. Saturday and was felt across much of the Oklahoma City metropolitan area.







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