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.
Today’s paper round-up is rather short. Maybe this is due to the start of the field work season and many editors being involved in field research, maybe it’s just holiday season. Maybe I’ve missed some papers because I have been in the field, too. However, there are some very interesting studies, especially concerning tsunamis. Enjoy reading and please tell me what I’ve missed in the comments.
It’s June and it’s time for a new paper round-up, isn’t it? When I compiled the list during the past weeks I already realized that there’s a lot of new literature out there, and I guess this month’s post is probably the longest list we’ve ever had – 21 articles! So here are the latest papers on paleoseismology, tsunamis (maaaany tsunami papers this time), and active tectonics. As always: Any suggestions are highly appreciated. Enjoy reading!
Some weeks ago we published a new study on the classification of earthquake-induced landslide event sizes based on seismotectonic, topographic, climatic and geologic factors. Our idea was that this classification could be used to help improve seismic hazard assessment by contributing to a better prediction of landslide hazards induced by an earthquake when the geologic, topographic and climatic context is well defined. Possible applications could be the short-term prediction right after an earthquake or scenario modeling, e.g. for critical infrastructure. Since earthquake triggered landslide event sizes are also an important proxy for the estimation of magnitude and intensity of past earthquakes, I thought our study might be interesting for the paleoseismicity community as well, and so I put together a brief summary.
Between 1885 and 1938, the northern Tien Shan at the border between present Kyrgyzstan and Kazakhstan experienced a remarkable series of five major earthquakes, exceeding M6.9 and reaching up to M ~ 8 (1885 Belovodskoe M6.9, 1887 Verny M7.3, 1889 Chilik M~8, 1911 Chon Kemin M8, and 1938 Kemino Chu M6.9). Combined, the seismic moments add up to almost moment magnitude 9, which is a significant amount of strain released in roughly 50 years and across an E-W stretch of less than 500 kilometers. Even more intriguing is the fact that the ruptured region is located more than thousand km north of the nearest plate boundary and associated India-Eurasia collision zone. The macroseismic areas of these earthquakes include the present-day capital of Kyrgyzstan, Bishkek (Frunze) and the former capital and still largest city of Kazakhstan, Almaty (earlier names Alma Ata and Verny).
Continue reading “New papers on paleoseismology in the Tien Shan”
A team of Ecuadorian and French geologists has started to map the coseismic effects of the M7.8 earthquake that hit Ecuador on 16 April, 2016. The quake occurred at a depth of about 20 km and caused more than 600 fatalities, mainly in the area near Muisne. Two strong aftershocks of M6.7 and M6.8 shook the epicentral area on 18 May, among hundreds of smaller shocks that were recorded. The mapping is coordinated by the Instituto Geofísico. First results show earthquake environmental effects like liquefaction, mud venting, and surface cracks. Some impressions from the field work can be found here:
Today’s paper round-up covers a very wide spectrum of earthquake related studies. We have work on tsunamis, turbidites, and lake paleoseismology, paleoseismological data from Asia, Archaeoseismology, mud volcanoes, the ESI-2007 scale, and an explanation on what the rise of the Andes is driven by. Enjoy reading!
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!
This is the April edition of my paper round-up. Today I recommend papers on high-resolution topography data, fault mechanics, earthquake environmental/archaeological effects (liquefaction, rotated objects, landslides), Quaternary dating, a fault database for Asia, and tectonics of New Zealand and Martinique. Enjoy! Continue reading “New papers on paleoseismology, tsunami, and active tectonics (Apr 2016)”
The 4th International Colloquium on Historical Earthquakes and Macroseismology will be held from 2-3 May, 2016, in Vienna, Austria. Attendance is free of charge and registration is possible until 31 March. The meeting is organised by Christa Hammerl and Wolfgang Lenhardt and will be hosted at the Zentralanstalt für Meteorologie und Geodynamik. The exciting program is available now for download: 2nd circular (PDF, 500 kb).