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The IGCP project 639 deals with sea-level changes, coastal earthquakes, and inundation by storms and tsunami: “Sea-level changes: From minutes to millenia”. The first meeting in Oman will take place from 9-14 November 2016 and will cover all science under the IGCP project 639 banner. Make sure to put this on your agenda if you’re interested.

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Tsunamis are a very real threat in the Indian Ocean. Most people will immediately think of the 2004 tsunami and the Sumatra subduction zone, but the Arabian Sea has seen strong tsunamis in the past, too. In 1945, a major earthquake at the Makran Subduction Zone caused a large tsunami (Hoffmann et al., 2013a). In 2013, the on-shore Balochistan earthquake caused a submarine slide which in turn triggered a tsunami that reached the coast of Oman (Heidarzadeh & Satake, 2014; Hoffmann et al., 2014a). There is also evidence for paleotsunamis along Oman’s coast (Hoffmann et al., 2013b; Hoffmann et al., 2014b). Now a team of scientists from RWTH Aachen University (Germany) and GUtech (Muscat, Oman) have published a tsunami inundation scenario for Muscat (Schneider et al., 2016). This is lead author Bastian Schneider’s guest blog on this research: 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

On 24 September, 2013, a magnitude 7.7 earthquake occurred in Balochistan, Pakistan. The quake caused intense ground motions and had dramatic consequences – hundreds of people died, and more than 100,000 lost their homes. A secondary effect which caught much attention in the international media was the birth of an island off the Pakistani coast – Zalzala Jazeera or Earthquake Island. Another effect which went almost completely unnoticed was a small tsunami in the Arabian Sea. The tsunami reached wave heights of around 1 m at the Omani coast. In a paper which was recently published in Geology, my colleagues and me document the tsunami effects in Oman. We conclude on a submarine slide off Pakistan as the likely trigger mechanism.

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A good number of interesting papers has been published during the last months, related to active tectonics, paleoseismology and tsunami research. Study sites include Oman, Italy, New Zealand, California, Cascadia, Scotia Sea, and Central Asia. Enjoy reading and tell me, if you miss some publications here!

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I came across several interesting papers on paleoseismology and related disciplines, most of them published recently. They deal with “classical” paleoseismology, with earthquake environmental effects like coseismic landslides and tsunamis, and also with geomorphological indicators for active faulting. Let me know if I missed some! more

Annals of Geomorphology has now published a new volume on Paleotsunamis in its Supplementary Issues. Issue 57 (4) is all about Reconstructing and modeling palaeotsunami events by multi-proxy geoscientific analyses. The volume is an outcome of the 2011 Corinth conference and edited by Andreas Vött, Klaus Reicherter and Ioannis Papanikolaou. I especially like it not only because I’ve organized the conference, but also because I am familiar with some of the study sites. Finally, I am co-author of the last paper. more

Update: Read the article of The Times of Oman here!

Today at 11:52:50 UTC a magnitude 6.3 earthquake occurred in SW Iran close to the shore in a depth of 10 km. The event was widely felt in Iran and across the NE Arabian Peninsula. Moment tensor solution reveal a thrust mechanism, which is in perfect concordance with the historic seismicity pattern. The event was caused by the convergence of the Arabian and Eurasian plates, that not only built up the impressive Zagros Mountains, but also lead to the formation of the Makran Subduction Zone. Relative plate motions there are as fast as 20 mm/yr in the central part. more

I am currently at GUtech in Oman, a sister university of RWTH Aachen University, for teaching Geophysics and I spend most of the free time in the field with my colleague Gösta Hoffmann. On Friday we went to the Batinah area NW of Mascat to look for active faults. The Batinah is a plain of most likely Quaternary age, made up from the sediments delivered from the huge mountains in the south. Folded Tertiary limestones are cropping out close to the mountain range. Some of them are covered by Quaternary gravels, others aren’t. 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