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Marta Ferrater from the Universitat de Barcelona did a lot of research on the Alhama de Murcia Fault. Her most recent paper deals with how good we can measure lateral offsets along faults which move only very slowly. This is probably of great interest for many people working on slow faults, so I am glad that she agreed to write the following guest post: more

Our colleague Efthymios Lekkas kindly uploaded a new report on the recent South Lefkada Earthquake. If you can read Greek, have a look at this website: http://www.edcm.edu.gr/. Alternatively, you can download the slideshow from his personal website here as a PDF: http://www.elekkas.gr/images/stories/Frontpage/2015_Lefkada/lefkada2015.pdf

The PDF contains info on the tectonic setting, historical and instrumental seismicity, followed by a collection of the earthquake (environmental) effects. more

We published a new study dealing with paleoseismological work on the Milesi Fault near Athens, Greece. A slip rate was estimated based on GIS work, mapping, and trenching. Four surface-rupturing earthquakes in the last 4-6 ka were found, and we estimate magnitudes of around M6.2. With these input parameters, we developed a seismic hazard scenario that also takes into account site effects. Our results show that the official seismic hazard zonation in Greece, which is based on instrumental and historical records, contradicts geological data. We also show that extension in this region is not only confined to the Southern Evoikos Gulf graben system, but a significant amount of extension is accommodated by active faults closer to Athens. more

RWTH Aachen University seeks, as soon as possible,
a geoscientist (f/m) with a background in neotectonics, GIS and Remote Sensing skills for a PhD position in the research project ALMOND („Albania and Montenegro Neotectonic Deformation“). This project is a collaboration between RWTH Aachen University and the Friedrich-Schiller-Universität Jena and is funded by the German Research Foundation (DFG).

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I’ve spent several weeks in Eastern Kazakhstan this summer for paleoseismological field work. During the first part of this trip we looked at some thrust and strike-slip faults in the Ili Basin and the Saty area. The second part was almost entirely devoted to study the Dzhungarian Fault. I’ll blog about this second part later. Eleanor, David, Austin and me were the UK representatives in our team. We were so lucky to have Kanatbek from Kyrgyzstan and Aydin from Kazakhstan with us. They did not only lead us to all the interesting places and helped us to understand the geology and the tectonics, but they also did a fanatastic job organizing the field trip and dealing with the local surprises, which as you know happen in basically every field trip.

Our first study site was located at the northern boundary of the Ili Basin, where we did some work last year already. more

The Canyonlands National Park, Utah, is famous for its beautiful landscape and spectacular landforms. For many geoscientists it is also well-known as a sandstone reservoir analogue and as a tourist you’ll often run into groups of geologists on field trips. It’s a matter of debate how and how fast the beautiful grabens in the Needles Fault zone formed – these are large arcuate canyons several tens of kilometres in length, paralleling the Colorado River. In a new paper we present results from remote sensing, mapping, and georadar (GPR). Our aim was to better understand the coupling between deformation, erosion and deposition in such an active system. Based on our findings we developed a model of graben formation and describe the geometry of the dilatant faults at depth. We argue that either the grabens are older than previously assumed or that sedimentation rates were much higher in the Pleistocene.

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In the last two posts I have reported on the scientific sessions of the Fucino15 conference and on the first of the field trips. This post is about the L’Aquila field trip. I haven’t been to this city before and I was curious to see the place that sadly became so famous in earthquake science. I was surprised by how many heavily damaged buildings were still standing and by the overwhelming amount of historical buildings that await their reconstruction. We were given a great tour through the Palazzo Ardinghelli which is currently being rebuilt, then we had a look at the worst-affected parts of the city. Here’s a report in images. more

Our latest paper on coastal change in Oman deals with an extreme flood event that was recorded in an archaeological site in Ras al Hadd, at the easternmost tip of the Arabian Peninsula. We found multiple evidence for tsunamis that hit Oman’s coast in the past. Close to Fins, mega-boulders were thrown on a cliff by huge waves. Fine-grained sediments typical for tsunami action were found in the same area. Searching for further evidence, we came across the archaeological site of HD6 in Ras al Hadd. The archaeologists who were excavating this site told us about strange findings in the archaeological record – they encountered a layer that interrupted the otherwise continuous stratigraphy of the settlement. The bronze age fishing village is located very close to the coast only a few meters above sea level, a large tsunami could easily impact here. more

During the last three weeks I have been to Kazakhstan for paleoseismological field work and to summarize this journey: It was amazing! The trip was part of the Earthquakes without Frontiers project (EwF). This research project is funded by NERC and ESRC and aims on increasing the knowledge on earthquake hazards in Central Asia. The field work was lead by Richard Walker and scientists from Kazakhstan, Kyrgyzstan, and the UK had a close look at fault scarps in the easternmost parts of the country. Our aim was to determine the slip rates of some of the longest and most prominent thrust and strike-slip faults in the area. more

This summer and fall will be trenching time, our Belgian, Dutch and Austrian colleagues are opening paleoseismological trenches. The DEM/image of the last post by Christoph shows already some morphological relevant faults in the Aachen area (recognized by the rectangular open-pit lignite mines) that are striking NW-SE. more