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? Continue reading “Earthquakes and dust clouds”
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.
The public version of the EEE Catalogue, a global catalogue of environmental effects induced by modern, historical and paleoearthquakes, is available at http://www.eeecatalog.sinanet.apat.it/terremoti/index.php. This public version has been developed on Google Earth and aims at providing basic information at earthquake, locality and site level, including the rupture zones (when available) and the local description of environmental effects, integrated by some imagery (photographs, stratigraphic logs, etc.). Continue reading “Public version of the EEE Catalogue online!”