Thursday, April 12, 2012

"Western Coast Of North American Continent Is Shaking"

That headline comes from the "Earthquake Report" and provides for an accurate summary of the situation as the earthquake story continues to grow. Below are just a few samples of articles in circulation - all discussing this emerging earthquake story.

Epicenter location see below in list
143 km (89 miles) NE (48°) from Guerrero Negro, Baja California Sur, Mexico
The whole western coast of North America is currently very instable. Earthquakes from Mexico until Oregon via the Gulf of California.
Update 07:36 UTC : USGS has upgraded this ridge earthquake to a 6.9 Magnitude (from M7.0 earthquake-report calls the earthquake “massive”). We are currently setting up an in-depth report on this earthquake. It will be online in a couple of minutes.

Continuous aftershocks are hitting an area of 300 by 300 km to the West of Sumatra.

EMSCBaja California, MexicoApr 12 07:15 AM6.360.0MAPI Felt It
  • Sonora, Hermosillo - Very weak shaking indicated
  • Hermosillo Sonora Mexico - Light shaking indicated
  • Hermosillo - Very weak shaking indicated
  • Hermosillo, Sonora Mexico - My computer monitor and my fish tank were shaking and i heard a berry weard sound
  • Bahia de Los angeles - On the coast of Bahia de Los Angeles staying in a 3 story building. Very strong shaking through both of these woke everybody up fast. Hoping this is it, not sure if this building can take more than it already got. Considering getting out for fear of another one hitting that's worse.
  • GEOFONBaja California, MexicoApr 12 07:15 AM7.010.0MAPI Felt It
    USGSGulf Of CaliforniaApr 12 07:15 AM6.910.3MAPI Felt It
    GEOFONBaja California, MexicoApr 12 07:06 AM6.110.0MAPI Felt It
    USGSGulf Of CaliforniaApr 12 07:06 AM6.210.1MAPI Felt It
    EMSCGulf Of California

    The world-wide list of significant earthquakes is found in this article above, but it is too long to place here. Open the link and take a look, it is astonishing.

    A strong earthquake struck off the coast of Mexico on Thursday, waking up residents living near the Gulf of California, only hours after a separate temblor swayed tall buildings in Mexico City, causing evacuations.

    The U.S. Geological Survey reported a 6.9 magnitude quake hit the waters between the Baja peninsula and the northern state of Sonora at 12:15 a.m. local time.

    Earthquake overview : A very strong ridge earthquake has hit the sea floor of the Gulf of California. The shaking will be extended onto the coastal areas like the Mexican continent and Baja California peninsula
    The earthquake was felt strongly. There have been 2 confirmed reports in San Luis of a VI intensity (72km from the epicenter). This means that there is the potential for VII-VIII in the epicentral area (damaging).

    Two strong and shallow earthquakes struck Gulf of California on April 12, 2012. First earthquake was measured with magnitude 6.2 at 07:06:01 UTC with depth of 10.1km. A second earthquake struck same area less than 10 minutes later, at 07:15:49 UTC, recorded magnitude was 6.9 with depth at 10.3km.

    The set of earthquakes in the Gulf of California have started with a M4.7 earthquake, followed 18 minutes later by a M6.2 earthquake and another 9 minutes later with a M6.9 earthquake (the most powerful so far)

    Although it is a ridge earthquake, the epicenter of the M6.9 quake looks to be very close to the coast which makes this earthquake (the second very strong in a matter of 9 minutes) EXTREMELY DANGEROUS for shaking damage and fatalities. Let us hope that we are too pessimistic here. The kind of shaking will depend on the focal mechanism.

    Following calculations by the USGS (providing that the earthquake data are correct) a MMI VII will have been experienced on the Baja California peninsula ! This means dangerous for the coastal areas experiencing this kind of shaking.

    A strong earthquake hit Mexico on Wednesday, shaking buildings and sending people running out of offices onto the streets of the capital Mexico City. The U.S. Geological Survey said the 6.5 -magnitude quake was centered on Mexico’s Pacific coast near Michoacan and struck fairly deep under the earth at 65 km or 40 miles. Prior to the Mexico earthquake, a powerful and shallow 5.9 struck near the Juan de Fuca tectonic plate off the coast of Oregon- indicating tectonic plates worldwide are being rattled by planetary seismic tension. Prior to Oregon earthquake, two massive 8.0+ magnitude earthquakes (8.6 and 8.2) struck the ocean floor off the north coast of Sumatra, Indonesia.

    ...the power unleashed in these seismic events is growing.

    This is testament to the dangers and seriousness of the earth-changes facing us and how these events are unleashing more unbridled force with each successive eruption. The Indian Ocean strike-slip fault earthquakes are very unusual. As a matter of fact, I’ve never heard of a strike-slip lateral earthquake of this great a magnitude; especially under water. Preliminary assessment of the Indonesian quakes by U.S. geologists suggests one plate lurched past each other as much as 70 feet. San Andreas is a strike-slip, lateral- can we even imagine two sections of ground moving 70 feet near San Francisco?

    Just so we understand the significance of what transpired today; the Japanese March 11, 2011 earthquake move the ocean floor 79 feet sideways and 10 ft upwards, but today’s earthquakes happened in double 8.0+ magnitude sequence and moved the earth nearly as far. Worst, the seismic tension from the event ricocheted around the world and contributed to other earthquakes.

    The massive earthquake off Indonesia surprised scientists: Usually this type of jolt isn’t this powerful. The biggest earthquakes tend to occur in subduction zones where one plate of the Earth’s crust dives under another. This grind produced the 2004 magnitude-9.1 Indian Ocean disaster and the magnitude-9 Japan quake last year.

    Wednesday’s magnitude-8.6 occurred along a strike-slip fault line similar to California’s San Andreas Fault. Scientists say it’s rare for strike-slip quakes, in which blocks of rocks slide horizontally past each other, to be this large.

    “It’s clearly a bit of an odd duck,” said seismologist Susan Hough of the U.S. Geological Survey in Pasadena, Calif.

    Wednesday’s quake was followed by a magnitude-8.2 aftershock. Both were strike-slip quakes.

    “A week ago, we wouldn’t have thought we could have a strike-slip earthquake of this size. This is very, very large,” said Kevin Furlong, a professor of geosciences at Penn State University.

    So large, in fact, that the main shock went into the history books. Record-keeping by the USGS National Earthquake Information Center ranks Wednesday’s shaker as the 11th largest since 1900. It’s probably the largest strike-slip event though there’s debate about whether a similar-sized Tibet quake in 1950 was the same kind.

    A preliminary analysis indicates one side of the fault lurched 70 feet past the other — a major reason for the quake’s size. By contrast, during the 1906 magnitude-7.8 San Francisco earthquake along the San Andreas — perhaps the best known strike-slip event — the ground shifted 15 feet.

    The Sumatra coast has been rattled by three strong strike-slip quakes since 2004, but Wednesday’s was the largest

    As seen in today's seismic monitor, there was also a 4.8 magnitude in Utah and a very unusual 4.5 magnitude quake near the northeast part of Canada.

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