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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

It’s been a while since the last Friday links, so today’s list is rather long. Of course the Russian meteoroid-meteor-meteorite (yes, in this order!) was an absolutely amazing, though destructive phenomenon. The air blast was registered equivalent to an earthquake of magnitude 2.7. Read Livescience’s article here and read this text to get to know about meteors and seismograms in general. more

Several paleoseismology papers have been published in the latest issue of BSSA (103-1). There’s interesting new data on faults in New Zealand, California, and several regions in China, Taiwan and India. For sure I will read the following papers: more

In the last twelve hours, a series of major earthquakes struck the Santa Cruz Islands. Beginning with the activation of a thrust fault with a M8.0 (M7.9) earthquake, almost fifty aftershocks hit the region. A regional tsunami warning was released short six minutes after the first quake at 1:12 UTC and has now been cancelled.

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We’ve seen several magnitude 6 earthquakes last week. On 28 Januar, a shallow M6.1 strike-slip event occurred in eastern Kazakhstan. A little surprise only, we knew about thrust mechanisms in this area, but of course some strike-slip movements do not change the big picture. Would be interesting to check for surface ruptures. This is, by the way, the study area of our friend and colleague Angela Landgraf. Maybe we can convince her to write something about the paleoseismological background of that area? more

Something many people have been waiting for happened last week. Judge Marco Billi explained his verdict in the L’Aquila case. In a 950 page document he published the so-called “motivazione”, stating that “the deficient risk analysis was not limited to the omission of a single factor, but to the underestimation of many risk indicators and the correlations between those indicators.” This should have been understood by the scientists, but instead they delivered a “superficial, approximate and generic” analysis. more

Annals of Geophysics’ latest Special Issue 55-5 is focussed on Earthquake Geology: Active tectonics in the Mediterranean and Europe: site studies and application of new methodologies. This issue was edited by L. Cucci, P. M. De Martini, E. Masana, and K. Vanneste and contains seven papers. As always, all articles are open access. more

Geographical Information Systems (GIS) are one of the most important tools in geosciences and can be helpful in almost every discipline. They are widely used not only in academia, but also in industry and administration. Obviously, it’s a good idea to know how to use these softwares. There are dozens, if not hundreds of different GIS versions available, but only few of them are freeware, like QGIS. Our colleague Riccardo Klinger from Digital Geography started a crowdsourcing initiative to get money for creating a free online video tutorial for everyone who wants to learn QGIS. If you like this idea, support him here at startnext.de. more

The RealClimate blog network published two long articles on the state of the art of sea level rise estimations. Part 1 was written by Stefan Rahmstorf on 9 Jan, part 2 was posted today. What will we need to prepare for until the end of the century?  more

The collapse of Bronze Age civilizations c.1200 BC remains a persistent riddle in Eastern Mediterranean archaeology. Earthquakes, attacks of the Sea Peoples, climatic deterioration, and socio-political unrest are among the most frequently suggested causes for this phenomenon. In the last issue of Seismological Research Letters (January/February 2013), Manuel Sintubin and myself attempt to retrace the origins of the idea according to which earthquakes may have caused the demise of Late Bronze Age Eastern Mediterranean societies. The article features reproductions of unpublished archival documents held by the Cyprus American Archaeological Research Institute (Nicosia). The free-access version of the paper can be found here. Happy reading!