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The Chilik-Chon Kemin Fault Zone is a major left-lateral strike-slip fault zone in Kazakhstan and Kyrgyzstan, just a few tens of kilometres east of Almaty and north of Lake Issyk Kul. It has seen one of the largest continental earthquakes ever recorded in 1889, with an estimated magnitude of ~M8.3. In July and August I had the chance to visit this fault zone for two weeks together with Angela Landgraf from Potsdam and Aidyn Mukambaev from the National Data Centre, thanks to a travel grant from COMET (thanks so much, COMET!) and with support from the EwF Project. We wanted to find out more details about the tectonic geomorphology of this fault zone and we wanted to study the slip rate and earthquake recurrence intervals. So we took our drone, shovels and picks and set off for a field trip into the mountainous wilderness. Since I will leave for another field trip to Kazakhstan (Dzhungarian Fault) tomorrow, I will leave you with some impressions from our field work and provide more information once the paper is published…
Enjoy!  more

Dear Colleagues,

We would like to bring your attention to a workshop we are organizing on the topic of Fault Displacement Hazard Analysis (FDHA). The Workshop will be held December 8-9th at the U.S. Geological Survey Campus in Menlo Park, CA, and is timed to be the Thursday and Friday before the 2016 AGU Fall meeting so that international participants can plan to attend both the Workshop and AGU the following week.

Workshop themes will include: more

The geometry, length, and displacement of fault ruptures that breach the surface provide critical information on the behavior of faults during seismic events (coseismic deformation), and on their long-term behavior. The study of coseismic fault ruptures has concentrated almost exclusively along continental faults, while submarine studies have been scarce, and only a few provided quantitative constraints in parameters such as fault displacement (e.g., Tohoku Earthquake). In addition to represent more than two thirds of the Earth’s seismicity, submarine faults can also be associated with tsunamis, potentially increasing the seismic hazard that these structures pose.

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On 16 April an earthquake of magnitude Mw7.0 hit the district of Kumamoto, Kyushu Island, Japan. The quake was preceeded by a Mw6.1 foreshock one day before. It occurred on the ENE striking, right lateral Futagawa-Hinagu fault zone. Our colleague Koji Okumura from Hiroshima University has prepared a short report on this surface-rupturing event. Download the report here (PDF, 612 kb). The report will be continuously revised and corrected, so check for regular updates. Thanks Koji for providing this summary!

I am quite happy that our new paper has finally been published in GJI. We worked on a fault between Aachen and Cologne in Germany and found that there has been a surface rupturing earthquake less than 9000 years ago, and possibly not much older than 2500 years BP. The area is of interest also because in 1755/56 a series of damaging earthquakes hit Düren and its surroundings – these are the strongest historical events in Germany that we know of. The quakes were felt as far away as Berlin, Strasbourg, and London, yet there were no primary ruptures. “Our” quake must have been much stronger… more

Our colleagues Stéphane Baize and Oona Scotti from the French IRSN finished a report on the 2014 Napa Earthquake: Post-seismic survey report, with special focus on surface faulting. On 24 August 2014, an earthquake of magnitude Mw6 occurred on the West Napa Fault in shallow depth. The quake caused significant damage, an interesting pattern of surface ruptures, and the immediate attention of hundreds of geologists. The primary and secondary effects were mapped only hours after the event, which turned out to be extremely important – a large amount of afterslip was recorded in the following days. The earthquake was not only recorded by a huge seismometer network, but the ground motion was also captured by GPS sensors and InSAR images. The new IRSN report is especially concerned with the surface faulting hazard, since this agency is responsible for the safety of nuclear installations in France.  more

The 16 World Conference on Earthquake Engineering will be held from 9-13 January, 2017, in Santiago de Chile. Note that the deadline for short abstracts submission is 23 November, 2015! Abstracts can be submitted via this link.

This meeting comes with a number of sessions which are interesting for earthquake geologists, paleoseismologists and those of us who deal with seismic hazard assessments. Among them: more

In 2013, a M_W7.7 earthquake struck Balochistan, caused a huge surface offset and triggered a small tsunami in the Arabian Sea. Immediately, the apparently strange fault behaviour caused the attention of scientists world wide and a number of papers were published. The discussion is highly interesting and still ongoing. This an interesting case for paleoseismologists, too, not only because of the cascading earthquake effects, but also because of the surface rupture distribution, from which we might learn some important lessons for our future work. Now my colleague Yu Zhou and his colleagues from Oxford University published a new paper on this event, arguing that it might be not as unusual as it seems. Their research is based on the analysis of Pleiades stereo satellite imagery, which has proven to be a very useful data source already. Yu send me a nice summary of his recent research: more

Last Friday the RAS held a discussion meeting on Tectonics from Above: Recent Advances in the Use of High-resolution Topography and Imagery in London. Almost the entire Cambridge Tectonics Group went there and I absolutely enjoyed the meeting and the discussion with friends and colleagues mainly from the UK and from France. The speakers reported on open-source software for producing high-res DEMs, advances in aerial and satellite imagery, new techniques in remote sensing, and latest developments in fault/offset mapping. The meeting was supported by NERC, COMET+ and LICS. more

The SSA 2015 meeting will take place in Pasadena, CA, from 21-23 April. As always, there will be plenty of interesting things for paleoseismologists. Scott Bennett asked me to advertise the following session that deals with a topic most of us will find highly important:

How Reliable Are Reconstructions and Models of Surface-Rupturing Earthquakes?

Abstract deadline is 9 January, 2015. more