Earth Changes
This record-breaking earthquake swarm is nothing to fear, however, according to the U.S. Geological Survey (USGS). Periods of tectonic unrest are common in the area and probably don't presage a larger quake, the USGS said.
Most of the quakes affecting this Bay Area city are tiny. The one that kicked off the swarm at 8:50 a.m. Pacific Time on Oct. 13 was a mere magnitude 0.8. People don't usually feel earthquakes until they reach a magnitude of 2.5; quakes between magnitude 2.5 and 5.4 can be felt but rarely cause much damage. Most of the quakes occur at depths of 5 to 6 miles (8 to 9.7 kilometers).
A handful of the San Ramon quakes have rattled locals, including a magnitude-3.6 quake that hit on Oct. 19 and a magnitude-3.1 quake recorded on Oct. 27, both causing weak to light shaking in the East Bay (the eastern part of the San Francisco Bay area). Between 11:30 a.m. PT on Oct. 22 and 11:30 a.m. on Oct. 23, 11 quakes hit the area. Five were between magnitudes of 2.0 and 2.9, and one was a magnitude 3.2.

Six team members from the Mablethorpe Coastguard were called out after the carcass was first spotted.
Coastal experts have confirmed that the large brown carcass spotted on the beach at Huttoft is a whale, but cannot yet identify which species it is.
However they have warned that the carcass could leak bodily fluids which are harmful to dogs.
A maritime operations officer for the east coast and Humber, said: "The local [coastguard] team has been out to the whale.
GeoNet reported the earthquake at a depth of 15km at first, which was updated to a much shallower 3km depth.
It was first reported as being 'moderate', which has since been changed to 'strong'.
Within 40 minutes of the quake there had been almost 160 'felt it' reports on the website. Most reporting it being 'light' intensity.
The centre of the earthquake was in the Aegean Sea, around 44 kilometres north of the Cretan city of Chania according to the Institute of Geodynamics. The depth of the earthquake is estimated at 30 kilometres.
The earthquake lasted for a few seconds and there have not been reports of any injuries or damages in Crete thus far, according to Greek media reports.
Crete is Greece's largest island and the country's most southern land point.
Three separate bouts of hail hit the town of Southern Cross and the surrounding farming district on Sunday night, wreaking havoc on crops ripe for harvest.
It was the second hail storm in as many weeks to dash the hopes of farmers at the end of what had been a relatively good season.
Agronomist Gary Kenwood of Southern Cross owns the only farm supply store in town.
In August, a waterspout was also witnessed in the Hai Phong northern port city and the southern province of Kien Giang.
A waterspout is an intense columnar vortex that occurs over a body of water. They are connected to a towering cumuliform cloud or a cumulonimbus cloud. In the common form, it is a non-supercell tornado over water.
Waterspouts have a five-part life cycle: formation of a dark spot on the water surface, spiral pattern on the water surface, formation of a spray ring, development of the visible condensation funnel, and ultimately decay.
Ms. Le Thi Xuan Lan, from the Hydro-meteorological Observatory of the Southern Region, said that in Vietnam, this phenomenon usually occurs at the beginning and during the rainy season and more in the south than the north, particularly in the sea of Rach Gia - Kien Giang - Tho Chu. However, waterspouts in Vietnam are not too strong.
A snowstorm hit Mohe, China's northernmost county in Heilongjiang Province, from early morning on Monday.
The depth of snow reached 8 centimeters (3.14 inches) by 17:00 and the heavy snow brought the visibility down to less than 100 meters (328 feet) as well. Vehicles have to slow down on snow-covered roads, while the local sanitation department dispatched snowplows to clear up the roads.
Spewing a slurry made of water and gases mixed with sand and dirt, the mud volcano shot several meters into the air as it started forming an artificial island on Sunday, just off the coast of the Taman Peninsula.
The act of nature was recorded by local beach strollers who witnessed the mud volcano, most typically formed after hot water below the earth's surface begins to blend with mineral deposits, pushing the mixture to the surface. But unlike an actual volcano, the muddy imitation produces no lava.

A resident walks past the rubble of a house after it was damaged by an earthquake in Mingora, Swat, Pakistan, on Monday.
The full scale of Monday's disaster and human toll was unclear when night fell over the remote and rugged terrain as authorities in Pakistan and Afghanistan rushed to mount rescue efforts.
In the most horrifying tragedy to emerge so far from the quake, 12 young Afghan girls were crushed to death in a stampede as they tried to flee their shaking school building.
The bulk of the casualties were reported from Pakistan, where 214 people were killed and more than 1800 injured, disaster management authorities said.
The quake was centered 1 mile east of San Ramon and struck at 10:13 p.m. The smaller one hit at 2:48 a.m. in roughly the same area.
The area has seen more than 200 small quakes in recent weeks, part of a swarm that started Oct. 15. Seismologists have said there isn't anything to fear over the swarm. They say the Calaveras Fault is releasing tension, and the chances of a quake above magnitude 6.7 is only 7 percent within the next 30 years.
For a map of the latest quakes and more earthquake resources, check out the SFGATE earthquake page here.













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