Burma experiences 6.8 Earthquake

Burma (Myanmar to its BFFs) experienced a large earthquake in its backcountry today near its borders with Laos and Thailand. Initially reported as a 7.0M earthquake by the US Geologic Survey, the quake was later downgraded to a 6.8M.

The earthquake occurred in a  relatively remote and sparsely populated region.  The death toll hours after the quake was reportedly low: a child in Burma, and a woman in Thailand.  However, a Burmese official in contact with Western press has stated that there could be more casualties in the town of Tarlay, which lies close to the epicenter.  In Tarlay 10 men, and 13 women, were killed when buildings they were in collapsed.   According to the official, five monasteries and 35 buildings collapsed in the town as a result of the earthquake.

A 4.8M aftershock occurred approximately half an hour after the first earthquake, and then an hour and a half after that a 5.4M aftershock occurred.

No tsunami warning was issued after the earthquake as it was too far inland for it to generate a wave in the Indian Ocean.

The BBC and several other news sources were reporting that two 7.0M quakes struck the region, seconds apart, and each with a different depth.  However, there was only one earthquake in that particular time-period, and it occurred at a depth of 10km (6.2 miles).  The Geological Survey initially said the quake had a depth of 230 km (142.5 miles), but it later revised its estimate to say the quake was 10 km.  This change is probably what led to some of the confusion in reporting on the earthquake.

Updated to reflect new death tolls from the quake

California Coastal Tsunami Inundation Maps

The California Geologic Survey has made their coastal tsunami inundation maps available via a Google maps overlay.  There is also a KML overlay for Google earth. 

As noted on the map page, the overlays are not as accurate the state's official tsunami inundation maps, however the official maps are also available online, and are viewable as pdf files by clicking on the red boxes in the google maps overlay.

The Next "Big One" won't be easy to Predict

Following the earthquake and tsunami events in Japan, some US media outlets have been busy trying to drum up interest/fear that the victim of next "Big One" is going to be California.  Especially guilty of this is Simon Winchester, who wrote an article for Newsweek where he makes the assertion that earthquakes essentially create mirrors of themselves.  According to Winchester, Japan's recent megaquake was a reflection of the 2010 Chilean Earthquake.  Following his logic, and I use that term loosely, the 2010 and 2011 Christchurch, New Zealand earthquakes will be mirrored in . . . you guessed it: California .  The geophysicist community hasn't been quiet about their disdain for what is essentially a pseudoscience and fear-mongering fluff piece meant to sell copy, and luckily both blogging and mainstream media organization have been willing to run more scientifically grounded articles as a counter.

It would certainly be great if it were that easy to predict earthquakes, but as Susan E. Hough, seismologist for U.S. Geological Survey, pointed out in a CNN article, "pointing to any one corner of the Earth as the location of the next Big One is not a winning game. Take a map of the world's most active plate boundaries and throw a dart; where it lands is as good a guess as any."

Rainy Weather Causes Mudflows on Indonesia's Mount Merapi

Residents of Sleman, in central Java, following mudflows into their village (source)

Just a follow up post on conditions around Indonesia's Mount Merapi, whose eruption I was writing on last year.

The Jakarta Post reports that recent heavy rains have sent a slurry of volcanic debris down the slopes of Mount Merapi over the weekend.  There has been no loss of life reported but 21 homes were buried in mud in the village of Sleman, and flood waters washed into the Argomulyo.  One family of three reportedly suffered burns, when they were late in evacuating, but these were likely chemical burns rather than thermal burns as mudflows of volcanic material can be slightly acidic.

Merapi is no longer erupting, but is still considered active, and the death toll since October now stands at over 350 people.

UPDATED: Gulf of Mexico Sheen Determined to be Sediment from Mississippi

Update: The U.S. Coast Guard has run an analysis of samples gathered from the sheen and found that is contained "only trace amounts of petroleum hydrocarbons, oil and grease." The Coast Guard added that, "at this point, the dark substance is believed to be caused by a tremendous amount of sediment being carried down the Mississippi River due to high water, possibly further agitated by dredging operations.

NOLA was reporting that the US Coast Guard was now investigating multiple reports of new oil sheen 20 miles north of the location of the 2010 Deepwater Horizon oil rig explosion.  The newly reported sheen lay about 30 miles from the Louisiana coastline and the mouth of the Mississippi river.

Photographer: Jerry Moran  (nativeorleanian.com)

Some reports on the size of the sheen stated that it was nearly 100 miles long and 12 miles wide.  According to NOLA, Paul Barnard, an operations controller for Coast Guard Sector New Orleans stated that, "We haven't been able to verify that, and it would be very unlikely for an individual to be able to observe a 100-mile long sheen."

As of today, the Coast Guard has stated that the sheen is most likely silty material stirred up from a dredging operation on the Mississippi River.  For the sake of precaution, they are having the material analyzed as it did possess a rainbow-like sheen similar to that associated with oil spills.  The Coast Guard spokesman said that it is possible that whatever the material is that is causing the sheen had been trapped in the sediment of the Mississippi's river bed, but was released by the dredging operation.

Cute Animated Video Explains Japan's Nuclear Reactor Situation

I really haven't touched on the specifics of the nuclear situation occurring in Japan.   This has been intentional on my part as analysis of events by "experts" in the field have been all over the board and I'm in no position to really delve into any sort of deep criticisms of what is being said.

That explanation out of the way, I just came across this video on reddit and had to share it.  It is a heavily simplified and animated explanation of what is occurring at Fukushima Daiichi.



Now, deconstructing a current event like a potential reactor meltdown into a pretty silly animation is something I consider to be pretty distinctly Japanese, and I don't know if it would be all that warmly received in the US.  But I do think that this method of presentation can be much better at explaining what is going on, and having it understood, than a talking-head scientist might be.

Nuclear Reactor Locations Compared to Global Earthquake Activity

Over on their site, MapTD.com has a created a custom google map showing the global distribution of earthquake activity with the locations of nuclear power plants superimposed. Based on data from the USGS,  averaging 175,000 4.5+ magnitude earthquakes since 1973, they've create a heatmap of global earthquake activity.  On top of that heatmap they've placed the location of  248 atomic energy plants.  With this I think people can get a better grip on how low the risk is to most of the world's reactors to seismic activity.  The above image is just a screen grab so head over to their site to look around at the map in more detail.

Japan Earthquake Swarm Animation

The Jumping Jack Flash blog (translation) made a Google Earth kml file (download) that creates an animation of the swarm of earthquakes that occurred around Japan between 6 March and 13 March 2011.

A quite well done video has been made of the animation, adding music and sound effects. 1 second in the video is equivalent to 1 hour. The animation starts on 9 March since the period between 6 March and 9 March was relatively quiet, seismically, around Japan. I recommend watching the video in full screen HD so that the dateline in the top left corner is readable.