Thursday, October 14, 2010

**Think of your faults the first part of the night,
when you are awake,
and the faults of others in the latter part of the night,
when you are asleep.**
Chinese Proverb

This morning -
None 5.0 or higher.

Yesterday -
10/13/10 -
None 5.0 or higher.

OKLAHOMA - ONE OF THE STRONGEST EARTHQUAKES ON RECORD IN OKLAHOMA rattled parts of five states Wednesday and left two people with minor injuries. The earthquake struck at 9:06 a.m. about six miles east of Norman in Cleveland County, sharply shaking portions of the Oklahoma City metropolitan area. The U.S. Geological Survey estimated the magnitude to be 4.3, but a research seismologist said the Oklahoma Geological Survey measured it at 5.1. The higher figure would make Wednesday's temblor the second-strongest here since records began. The quake was felt up to 170 miles away, at Bartlesville in northeastern Oklahoma and Wichita in southern Kansas. Reports also came in from Arkansas, Missouri and Texas. The Oklahoma Department of Emergency Management said it had received reports of minor damage, primarily to windows and due to items falling from shelves. Only minor damage had been reported through the city, mainly porches cracking or items falling off shelves. "The stuff on the wall shook. The dogs took off barking. I thought the world was coming to an end, to be honest."
A magnitude-5.5 earthquake struck El Reno, just west of Oklahoma City, in 1952, and another struck in northeastern Indian Territory in 1882. Quakes of 4.4 magnitude struck Hughes County in 1939 and Coal County in 1997.


Mystery of Mount Etna - Until now there had been many explanations for Mount Etna and that of the surrounding volcanics, but none had been able to explain the timing, origin and dynamics of the activity. Results from fluid dynamic models provide an alternative explanation for the existence of Mount Etna, its geological environment and evolution, as well as volcanism in the surrounding region. This theory suggests that Mount Etna is not directly the result of tectonic plate boundary activity, but that it resulted from decompression melting of upper mantle material flowing around the nearby edge of the Ionian slab that is slowly sinking into the Earth's mantle.
"Most volcanism on Earth occurs at plate boundaries in places where tectonic plates move apart (e.g. Iceland) and in places where tectonic plates come together with one plate diving (subducting) below the other plate into the mantle (e.g. Pacific ring of fire). For the latter scenario, the volcanoes form directly above the subducted plate." However, some volcanism, appropriately named intraplate volcanism, occurs far from plate boundaries and its origin is more controversial. "The chemistry of the volcanic rocks from Mount Etna and the nearby Iblean volcanics in Sicily and in the surrounding seas indicate that they are intraplate volcanics. Interestingly, the volcanics are located within a few hundred kilometres of, but are laterally offset from, the Calabrian subduction zone plate boundary, where the African plate sinks below the Eurasian plate. This suggests that the volcanics are somehow related to the Calabrian subduction zone. New modelling of subduction and mantle flow confirms this, showing that backward sinking of the African plate at the Calabrian subduction zone induced flow around the southern edge of the subducted plate and upward below Sicily. The upward flow induced decompression melting of upper mantle material and these melts extruded at the surface in Sicily, forming Mount Etna and the Iblean volcanics." Mount Etna is one of the most active volcanoes in the world and is in an almost constant state of activity. The most recent ash explosion occurred in August of this year, producing an ash plume that rose 800 meters above the crater edge.

-Tropical storm MEGI was 315 nmi WSW of Agana, Guam


Paula weakens as it approaches Cuba - The hurricane is about 30 miles from Cuba. A weakened Hurricane Paula is threatening to spread heavy rain across the Caribbean island. The storm's top sustained winds have dropped to about 80 mph (130 kph). It was moving north-northeast at near 3 mph (6 kph). The storm is forecast to track along the spine of Cuba. Cuba has issued a tropical storm warning for the province and city of Havana, and Mexico canceled all warnings on the Yucatan. A hurricane warning was in effect for Cuba's westernmost province, Pinar del Rio. A tropical storm watch was issued for the Florida Keys, from Craig Key westward, including the Dry Tortugas. Paula tipped the scales into hurricane strength Tuesday and intensified quickly to a Category 2 storm when its sustained winds topped 95 mph.
The Hurricane Center has described Paula as small. Its hurricane-force winds extend outward only up to 10 miles (16 kilometers) from the center and tropical strength-force winds extend outward up to 50 miles (85 kilometers). Paula is predicted to drop 3 to 6 inches of rain over parts of western and central Cuba, with maximum amounts of 10 inches in isolated areas. That could cause flash floods and mudslides. In addition, a storm surge is forecast to raise water levels by as much as 2 to 4 feet above normal levels along the coast of extreme western Cuba accompanied by "large and destructive waves."

PHILIPPINES - At least three potential cyclones, one of them still outside Philippine territory, are threatening the country, state weather forecasters said Wednesday. The other two are low-pressure areas (LPAs) inside Philippine territory. "Of the two LPAs in Philippine territory, the one east of Visayas has a larger chance of intensifying into a cyclone." It will be 24 hours until they can determine if the LPAs, particularly the one east of Visayas, will intensify into a cyclone. They are also monitoring a tropical depression still outside Philippine territory but moving westward toward the country. The first of the three potential cyclones to intensify or enter Philippine territory will be code-named "Juan".