Structural Geology and Tectonics of Hokkaido: Geometric principles, and the relationship between active and ancient deformation.During this course you will learn how geologic structures, developed from microscopic to map scale, reflect the rates, directions, and mechanics of past and contemporary plate tectonics and deformation. You will also hone your three-dimensional perception and skills through practical applications.
Posts in the category » Field work « ( 18 Posts )
An interesting post-grad student training course will be held from 26 June – 7 July, 2017, at Hokkaido University:
August 21, 2016 | in Field work
The Chilik-Chon Kemin Fault Zone is a major left-lateral strike-slip fault zone in Kazakhstan and Kyrgyzstan, just a few tens of kilometres east of Almaty and north of Lake Issyk Kul. It has seen one of the largest continental earthquakes ever recorded in 1889, with an estimated magnitude of ~M8.3. In July and August I had the chance to visit this fault zone for two weeks together with Angela Landgraf from Potsdam and Aidyn Mukambaev from the National Data Centre, thanks to a travel grant from COMET (thanks so much, COMET!) and with support from the EwF Project. We wanted to find out more details about the tectonic geomorphology of this fault zone and we wanted to study the slip rate and earthquake recurrence intervals. So we took our drone, shovels and picks and set off for a field trip into the mountainous wilderness. Since I will leave for another field trip to Kazakhstan (Dzhungarian Fault) tomorrow, I will leave you with some impressions from our field work and provide more information once the paper is published…
Ruptured pebbles are frequently found near and along active faults. At RWTH Aachen University Christopher Weismüller has just finished his MSc thesis on ruptured pebbles in southern Spain. There, the NE-SW trending Carboneras Fault System meets the N-S trending Palomares Fault and ends. more
Guest blog by Javier Escartín (IPGP) & Frédérique Leclerc (EOS): Studying coseismic deformation along submarine faults
The geometry, length, and displacement of fault ruptures that breach the surface provide critical information on the behavior of faults during seismic events (coseismic deformation), and on their long-term behavior. The study of coseismic fault ruptures has concentrated almost exclusively along continental faults, while submarine studies have been scarce, and only a few provided quantitative constraints in parameters such as fault displacement (e.g., Tohoku Earthquake). In addition to represent more than two thirds of the Earth’s seismicity, submarine faults can also be associated with tsunamis, potentially increasing the seismic hazard that these structures pose.
Between 1885 and 1938, the northern Tien Shan at the border between present Kyrgyzstan and Kazakhstan experienced a remarkable series of five major earthquakes, exceeding M6.9 and reaching up to M ~ 8 (1885 Belovodskoe M6.9, 1887 Verny M7.3, 1889 Chilik M~8, 1911 Chon Kemin M8, and 1938 Kemino Chu M6.9). Combined, the seismic moments add up to almost moment magnitude 9, which is a significant amount of strain released in roughly 50 years and across an E-W stretch of less than 500 kilometers. Even more intriguing is the fact that the ruptured region is located more than thousand km north of the nearest plate boundary and associated India-Eurasia collision zone. The macroseismic areas of these earthquakes include the present-day capital of Kyrgyzstan, Bishkek (Frunze) and the former capital and still largest city of Kazakhstan, Almaty (earlier names Alma Ata and Verny).
Guest blog by Sascha Schneiderwind (RWTH Aachen University): Multiparametric trenching investigations
[Update 15 February 2017: Since Sascha is an author here now, the post was attributed to him.]
Greece is one of the main targets of RWTH Aachen’s Neotectonics & Geohazards group. They worked on paleo-tsunamis, active faults on the Peloponnese, in Attica, and on Crete, and on the application of terrestrial LiDAR and shallow geophysics for active tectonics research. In their latest paper, Sascha Schneiderwind et al. developed a methodology to aid paleoseismic trenching studies. They use t-LiDAR and georadar to better and more objectively characterise lithological units. His paper includes nice examples from Crete and from the famous Kaparelli Fault. Here is his guest blog: more
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
A few weeks ago, Nadine Reitman (USGS) published an interesting paper about the use of Photogrammetry for Paleoseismic Trenching in BSSA. In this guest blog she shares her key findings and explains how to minimise errors without spending too much time measuring control points. Thanks Nadine!
Structure-from-motion (SfM) is now routinely used to construct orthophotos and high-resolution, 3D topographic models of geologic field sites. Here, we turn SfM on its side and use it to construct photomosaics and 3D models of paleoseismic trench exposures. Our results include a workflow for the semi-automated creation of seamless, high resolution photomosaics designed for rapid implementation in a field setting and a new error analysis of SfM models. more
Just a friendly reminder that the deadline for abstract submission for the EGU general assembly 2016 in Vienna is tomorrow, January 13th at 13:00 CET/12:00 GMT. If you are still looking for a session to submit your abstract to, please have a look at our session about Active Faults and the Earthquake Cycle (TS4.2/NH4.16/SM3.8)
By the way, the Vienna Basin is the perfect place to discuss active faults, as you see on our newest gravel pit outcrop. If you interested in having a closer look at this fault during the EGU – let me know…
Hopefully see you soon in Vienna,
Esther, Kris, Matthieu, Angela
November 8, 2015 | in Field work
The first part of my report on the field work that I did in Kazakhstan this year focussed on the stuff we had done in the South. Here is part II which is all about the Dzhungarian Fault. You’ve never heard about this fault? That’s easily possible. There are only very few papers that deal with this fault. In the 1960s Soviet geologist V.S. Voytovich published results from extensive field work on this fault (Voytovich, 1965; 1969). 40-50 years later a few studies on geodesy and geodynamics covered the broader study area and Shen et al. (2003) did some work in the Chinese part of the fault, but it took until 2013 before Campbell et al. revisited the Kazakh side and came up with new field data. They focussed on the tectonic geomorphology of this structure and determined a slip rate. Given this little amount of research done one would assume that the fault is not very large and of minor importance, but the opposite is true. The fault is around 300 km long in its Kazakh section and probably twice as long in total! more