An interesting paper has been published in Nature Geoscience by Murphy et al.: Limit of strain partitioning in the Himalaya marked by large earthquakes in western Nepal. It doesn’t happen too often that paleoseismological papers are published in this journal and it’s also not too often that authors publish such beautiful photos. The authors identified a more than 60 km long rupture in W Nepal with 10 m of surface offset (strike-slip with a normal component). 14C dating points to seismic activity between AD 1165 and 1400. That’s pretty surprising for many reasons: more
On 15 October, 2013 a shallow Mw7.1 earthquake occured in Bohol, Philippines. The quake caused more than 200 fatalities and severe damages. Instrumental intensities of VIII – IX were recorded and the USGS estimates the maximum slip to be around 120 cm. Stéphane Baize from the French IRSN created a report not only on the seismological and tectonic background of the earthquake, but also on the earthquake environmental effects (EEEs) that were caused by the event. more
A new paper by Esposito et al. has been published in Springer’s Landslide Science and Practice that will help to better constrain intensities on the ESI scale. Landslides induced by twelve moderate to strong earthquakes events during the last 300 yrs have been analyzed. The authors calculated distance vs. magnitude and distance vs. ESI epicentral intensity relationships, similar to the famous correlations by Keefer (1984). more
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
The final program of the 3rd INQUA-IGCP 567 Workshop to be held at Morelia (Mexico) from 19 – 23 November 2012 is out now!
Download the pdf here: PROGRAM MORELIA 2012 INQUA WORKSHOP
Check Acambay1912.org for latest news!
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The German research vessel R/V Polarstern is an ice-breaking mega laboratory and the heart of the German arctic and antarctic research. It is maintained by the AWI Bremerhaven (Alfred Wegener Institut for Polar and Marine Research). When I studied Geophysics at Leipzig University, I had to chance to visit this great ship during an excursion. Now the Polarstern is on her way for the Antarctic again, and this time the ship and the crew will spend the winter down far south for the very first time. Follow their campaign via the AWI blog or the GEO blog.
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For me the most important geo news this week was the court decision on the L’Aquila trial on Monday. A local court sentenced six scientists and one official for manslaughter to six years in prison – 2 years more than claimed by the prosecutor. Even though the scientists may not have found the best words to describe the earthquake hazard in L’Aquila, the decision is ridiculous in my opinion and caused an outcry throughout the scientific community. Especially the consequences for any risk assessment and public information might be fatal. I am really concerned. In the following I link to some blog posts that I found particularly interesting:
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Annals of Geophysics, the former Annali di Geofisica, published its latest issue today, dedicated to the 2012 Northern Italy earthquakes: Vol 55, No 4 (2012): The Emilia (northern Italy) seismic sequence of May-June, 2012: preliminary data and results. On 20 May 2012 an earthquake with a magnitude of Mw6.1 hit Finale Emilia, on 29 May an Mw5.8 event followed. The earthquakes caused a number of fatalities and significant damage. Earthquake environmental effects were widely observed, too. more
Our colleagues from the Bulgarian Academy of Science, Geological Institute “Strashimir Dimitrov“, have published a report on the coseismic and secondary effects of the May 22, 2012 Pernik earthquake, Western Bulgaria. The earthquake had a magnitude of MW5.6, see this special website of EMSC. Radulov et al. report intensities of up to VII (MSK) and various coseismic and secondary earthquake effects. more
Three papers published recently caught my eyes. First, Andrej Gosar investigated the earthquake environmental effects (EEEs) of the 12 April 1998 Mw =5.6 Krn Mountains earthquake, Slovenia. The quake measured VII-VIII on the EMS-98 scale, and Andrej found that the intensities reached the same values on the ESI2007 scale. He reports that the intensity distributions for both scales are comparable, but show some differences due to the sparsely populated epicentral area. The research concentrated on rockfalls for EEE determination. It’s a nice example that also moderate events can be characterized using the ESI2007 scale.
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