Let’s see, this is my 1st post here, thanks again for the invitation. Today, an interesting story circulated through mass and science media. The article by Kremer et al. published yesterday in Nature Geoscience presents geophysical and sedimentological evidence of potential tsunamis in the rather exotic environment of Lake Geneva. This phenomenon is not new at all and has been investigated by others before, but I pretty much share the authors conclusion, that the hazard of tsunami-like events in continental lakes deserves higher attention in the future.
Two papers on man-made earthquakes have been published last week and both have had received media coverage. Especially now, few days after the L’Aquila trial, the public is interested in any earthquake story and so the new findings that severe earthquakes happened due to human action caused some attention. Additionally, it caused me a headache and triggered not an earthquake, but a feeling of anger. Let’s talk about some good examples for bad science communication. more
Nature published three articles on the Sumatra April 2012 mega-strike-slip earthquakes. I am pretty sure that at least one of them will be discussed intensely. Earlier this year, two earthquakes with magnitudes of M8.6 and M8.2, respectively, occurred in the Indian Ocean off Sumatra. The epicentres were close to the epicentral area of the 2004 Christmas event, but further to the SW and entirely on the Indo-Australian plate. This was surprising for many reasons: We did not expect such strong strike-slip quakes, we did not expect them to happen intraplate, and we were surprised by the complex en echelon and orthogonal fault pattern. more
Two new tsunami papers have been published recently, and I am happy to be co-author of one of them. In Hoffmann et al. 2012 we report on our observations along the NE Omani coast between Fins and Sur. We found a ridge of imbricated boulders parallel to the coast, but in heights of several meters above m.s.l. on top of a cliff and dozens of meters inland. Also, extremely large blocks clearly stemming from the cliff were found. We used LiDAR to determine the mass of very large blocks (up to 40 t) and found this method to result in far lower weights than estimated with the classical method. more
The Sparta Fault in Greece is marked by one of the most impressive mountain fronts I’ve ever seen. A huge (yes, huge!) fault scarp has developed, traceable for kilometers; the fault itself is more than 60 km long. Ancient Sparta has been devastated by the last known major (M>7) earthquake that happened at this fault in 464 BC. Now, Papanikolaou et al. have published new data on this fault. They examined how paramaters like throw, segmentation, and catchments vary along strike and created a new seismic hazard map, showing a site-specific long-term recurrence interval of ~1.8 ka (+/- 450 a). more
A new paper has been published online first by Hinzen et al. on their archeoseismological study in Cologne, Germany. During recent archeological excavations, a number of damaged structures from Roman to Medieval times have been discovered and described among them a synagoge, the Praetorium, and a Roman well. Since damaging historical earthquakes are documented for the Lower Rhine Embayment, seismic shaking was a good guess to have caused the observed damage. more
After I came back from one week of holidays I checked the latest papers. Surprisingly, one was by myself! Finally IOP published our work on combined geoscience techniques in the Orkhon Valley, Central Mongolia. We used Georadar, SQUID-gradiometers, capacitive-coupled geoelectrics, octocopter stereoimages, shallow drillings, datings, and archaeological excavations for an geoarchaeological project. Using geophysical, archaeological and geological observations, we assumed a dating in the Turk/Uighur period (6th–9th century AD) and a re-use under Mongolian reign (12th–17th century AD). This would mean that this site is the furthermost walled structure in the peri-urban area of Khar Balgas. more
Although I already recommended some papers earlier this week, I have two more to mention: Supawit Yawsangratt and colleagues published new data on “Evidence of probable paleotsunami deposits on Kho Khao Island, Phang Nga Province, Thailand”. Nat Hazards, 63,151-163, DOI 10.1007/s11069-011-9729-4 in a special issue dedicated to tsunami research. Ran et al. presented work on the Wenchuan EQ epicentral area: “Paleoseismic events and recurrence interval along the Beichuan -Yingxiu fault of Longmenshan fault zone, Yingxiu, Sichuan, China.” Tectonophysics (2012), doi: 10.1016/j.tecto.2012.07.013. more
It’s holiday season, and many avid readers might need an advice on new books. Here’s one for the earthquake community: Primary Fault by Sharon Kae Reamer. The title reminds you of geology? This is no coincidence. The author reminds you of geology? Right! Sharon Kae Reamer is a seismologist, currently working at the seismological observatory of Cologne University. You probably know her work when you are into archaeoseismology, seismicity in Germany, or seismotectonics. Now she has published her first novel, and seismology does play a role. more
The coolest thing I’ve seen this week came from the British Geological Survey. They developed an app (for Android only) called iGeology 3D, which paints the geological map of your position around you. Yes, in 3D. Yes, only in the UK, but hey – great stuff! And it’s free, okay, it’s tax money… On Facebook, students are already stating that they will have a very easy mapping course next year. I can only hope that classical mapping (with compass, a map made up of paper, hammer, hand lens, acid and all that 20th Century stuff) will remain a basic course for all geoscience students. I’ve seen a geological compass app for a smartphone in the field recently, but it worked on very few hardrock surfaces only, because the owner didn’t want to dirty his mobile… more