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The latest issue (May 2013) of the Bulletin of the Seismological Society of America (BSSA) is dedicated to the Tohoku Earthquake and Tsunami of March 2011. The studies published therein deal with the source models of the megaquake and rupture dynamics, the ground motions, the tsunami propagation, earthquake triggered landslides and induced seismicity, earthquake environmental effects, and one paper presents a new proposal for an extended Tsunami Intensity scale. more

Last night (22:29 UTC on 22 April) a M4.5 earthquake rattled NE Hungary. The event was shallow (~10 km) and the epicentre was only about 25 km south of the city of Eger, famous for its red wine (Egri bikavér). The area is south to the Inner Western Carpathian Mountains. Light damage has been reported from the epicentral area, the EMSC questionnaires document intensities of VI. more

A very strong earthquake occurred in Eastern Iran close to the Iran-Pakistan border. USGS reports a magnitude of 7.8 and a shallow depth of 15 km, EMSC data suggest M7.7 and 50 km depth. Preliminary shake maps estimate intensities around MSK VIII, which would be enough to make traditional adobe buildings to collapse. Reports confirm the event was felt as far away as Muscat, Oman (600 km distance!). Update: USGS now also reports a depth of 80 km.

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Update: Read the article of The Times of Oman here!

Today at 11:52:50 UTC a magnitude 6.3 earthquake occurred in SW Iran close to the shore in a depth of 10 km. The event was widely felt in Iran and across the NE Arabian Peninsula. Moment tensor solution reveal a thrust mechanism, which is in perfect concordance with the historic seismicity pattern. The event was caused by the convergence of the Arabian and Eurasian plates, that not only built up the impressive Zagros Mountains, but also lead to the formation of the Makran Subduction Zone. Relative plate motions there are as fast as 20 mm/yr in the central part. more

On Monday morning, a M4.7 strike-slip earthquake rocked the Anza area, California. The quake occurred at the San Jacinto Fault Zone and was widely felt. As there are not many people who know the San Jacinto better than Tom Rockwell, I recommend to read this short interview. The LA Times has more info on the quake.  more

The following mail reached us today:

“A new International Graduate Summer Course in Iceland 2013:

EARTHQUAKE ENGINEERING AND ENGINEERING SEISMOLOGY
Iceland, 30 May – 21 June 2013
www.earthquake.is
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Today’s post of the Landslide Blog about a rockfall caused by a volcanic earthquake reminds me about something that’s in my mind for years already. Could we use dust deposits as a paleoseismological archive? Dust clouds of all sizes, ranging from tiny to huge, can be associated with seismic shaking, especially in arid and mountainous regions. Here I have collected a few videos I found on YouTube. When large amounts of dust settle they should form a distinctive layer recognizable in the sedimentary record, comparable to volcanic ash deposits. Of course they will be harder to be identified, since the material is the local one. I guess this could be done, similar to turbidites in marine paleoseismology. There are papers that describe changes in the aerosol content in the atmosphere after earthquakes, so why not look for them on earth? more

It’s been a while since the last Friday links, so today’s list is rather long. Of course the Russian meteoroid-meteor-meteorite (yes, in this order!) was an absolutely amazing, though destructive phenomenon. The air blast was registered equivalent to an earthquake of magnitude 2.7. Read Livescience’s article here and read this text to get to know about meteors and seismograms in general. more

Several paleoseismology papers have been published in the latest issue of BSSA (103-1). There’s interesting new data on faults in New Zealand, California, and several regions in China, Taiwan and India. For sure I will read the following papers: more

In the last twelve hours, a series of major earthquakes struck the Santa Cruz Islands. Beginning with the activation of a thrust fault with a M8.0 (M7.9) earthquake, almost fifty aftershocks hit the region. A regional tsunami warning was released short six minutes after the first quake at 1:12 UTC and has now been cancelled.

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