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Some good articles came up last week, and two interesting things happened in northwestern Europe. A small earthquake (M2.7-M3.4) hit northern Netherlands in the Groningen area and people claimed light house damages despite the low magnitude. The event was caused by natural gas production. The gas company, Nederlandse Aardolie Maatschappij (NAM), even has an online-formular for that! more

Yesterday, British media reported on a small tsunami that hit southwestern England at 10.15 BST. Wave heights reached around 30 cm in some bays but didn’t cause damages, BBC reports. Scientists from Plymouth University claimed an offshore landslide responsible for the rare phenomenon. The waves were seen in Cornawall, Devon and Hampshire. more

Today’s Friday links concentrate on tsunamis. Recently, Pure and Applied Geophysics came up with quite a lot of tsunami papers, and I am sure that this decision was made before the Japan tsunami happened. Some papers fur sure are interesting for analysing past tsunamis and earthquake environmental effects.

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A strong aftershock has rocked Japan on 11 April. USGS reported a magnitude of 6.7, while EMSC estimated M6.6. A tsunami warning has been released by the Japan Meteorological Agency for the eastern coast of Japan’s Honshu Island. UPDATE 13:06 MEST: The Tsunami warning has been cancelled. more

The Japan earthquake and tsunami have hit Japan harder than we could have imagined. Thousands are still missing, the death toll climbs and climbs, a nuclear disaster might happen or already happened, depending on who you ask, and the economical damages are incredibly high. Not only Japan was affected, but other countries as well feel the effects. Germany, for example, shut down seven of it’s oldest nuclear power plants and there’s a big debate on earthquakes and risks. The Geoblogosphere is still discussing lessons, estimations and consequences, and so are the official media. Here are some reports and opinions you should not miss. more

While the Japan earthquake has dominated the media obviously, some other news came up in geoscience. A researcher team lead by Ludovic Ferrierè who works at the Natural History Museum in Vienna claims to have proven the first impact crater in central Africa. The Luizi structure in the Democratic Republic of Congo was described in 1919 by a German study, but has not been confirmed as an impact crater for decades. Ferrierè and his team now found shatter cones and shocked quartzes, strongly pointing to an impact.  The crater has a diameter of 17 km and a 350 m high rim, which led the scientists to assume a meteor of 1 km diameter and a velocity of ~20,000 m/s. more

The Seismological Society of America has re-opened abstract submission for a special session on the Christchurch and Japan earthquakes during the Memphis conference. Deadline for new abstracts on this topic is 25 March.

The Seismological Society of America‘s annual meeting 2011 will take place in Memphis, Tennessee from 13 – 15 April.  A special focus is set on the New Madrid earthquakes, so paleoseismologists will definitely hear some interesting sessions there. Post meeting excursions are scheduled 16 April.  For more information visit the official website.

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Thanks to Alessandro I came across this incredible video of liquefaction occuring in the Tokyo Central Park during the M9.0 Japan earthquake. We can see a lot of very interesting features. First, cracks are opening, perfectly visible on the paved road and the cobble. Then we see the differential moving along those cracks, they are widening and narrowing and there’s vertical movement as well. Soon, the first ruptures appear in the meadows, despite the soft sediment there. more

The Japan M9.0 earthquake and the following tsunami are well documented by videos, photographs, sea-level measurements, seismograms etc. But how do we recognize such huge events if they happened some thousands of years ago? If there’s no historical report we would use earthquake environmental effects (EEE) for characterizing the earthquake and paleoseismicity. Let’s look what would be left from a 5000 year old earthquake and tsunami. more

An earthquake with a magnitude of Mw9.0 has occured 130 km east of Honshu, Japan in a depth of ~25 km. This had been the fourth or fifth strongest earthquake to be recorded by instrumental seismology. The quake caused significant destruction to the Honshu Island and triggered a tsunami that  destroyed a number of harbours. In some places (Sendai), tsunami heights were reported to exceed 10 m. A tsunami warning has been released for wide parts of the Pacific, but in Hawaii only 1 m was observed, therefore the warnings for the US West Coast have been lowered. more