Great news reached us from Spain! Our colleague Julián Garcia Mayordomo spread the news that an updated version of the Quaternary Active Faults Database of Iberia (QAFI) is now available online. QAFI has a GoogleMaps-based interface with clickable features providing loads of content on fault geometry, fault mechanism, slip-rate, historical and pre-historical seismicity, geomorphology, compilers, further references and much more. Truly a wonderful tool, congratulations!
Posts in the category » Centerfault « ( 24 Posts )
The San Andreas Fault Observatory at Depth (SAFOD) was one of the most ambitious (and expensive) experiments in the history of active fault research. A borehole was drilled through the San Andreas Fault, 3.2 km deep and 1.8 km in horizontal direction. The borehole was equipped with a number of instruments in order to get data from right where the earthquakes occur, but most of the instruments failed already in 2008 due to the extreme conditions. While analyses of the drill core resulted in some great scientific achievements and enhanced our understanding of fault zones, almost no one seems to have much interest in the in-situ instruments. Or let’s say, no one can pay the necessary amount for re-equipping the hole, millions of dollars… more
During the month of March 2014, Sascha and I along with Tobi and Lauretta (BSc students from RWTH University) were in Greece for fieldwork. The fieldwork campaign started on the island of Crete; our institute at RWTH Aachen has a joint project with Mainz University to carry out paleotsunami investigations on the island. The western part of Crete was uplifted by approximately 9 m during the 21st July AD 365 earthquake and also hit by the associated tsunami. Due to the strong seismic and highly tsunamigenic activity of the nearby Hellenic Trench, it is suggested that numerous earlier tsunamis have also struck the island. more
2013-12-30 | in Centerfault
During December, Greece has suffered from heavy rains and severe flooding. The following video shows a church near the town of Schinos (Skinos), which has been seriously affected by flooding and sedimentation. Many geology students and many paleoseismologists will find the church looking familiar, and I will explain why: more
Quaternary shortening at the Andean orogenic front (31°-33°S), Argentina: Current issues and challenges
Quaternary shortening at the Andean orogenic front (31°-33°s), Argentina: Current issues and challenges
Carlos Costa1, Emilio Ahumada1, Benjamin Brooks2, Andrew Meigs3, Lewis Owen4, Thomas Rockwell5, Lindsay Schoenbohm6, Carlos Gardini1, Héctor Cisneros1, Fabricio Vázquez1, 7
- Universidad Nacional de San Luis, Argentina. firstname.lastname@example.org
- U.S. Geological Survey, USA
- Oregon State University, USA
- University of Cincinnati, USA
- San Diego State University, USA
- University of Toronto, Canada
Outstanding exposures, new data, and novel hypotheses developed during the last decade have turned the frontal deformation zone of the Andes between 31°S and 33°S (Fig. 1) into one of the most promising areas worldwide for improving the understanding on mountain building processes and seismic hazards related to thrust tectonics.
Because the Andes are relatively narrow in these latitudes, the geodetic signal in the backarc is dominated by the subduction zone locking process at the Chile trench. Nonetheless the geodetic analysis provides some useful constraints on the location and rates of modern backarc shortening, though not necessarily on the vergence. It is currently understood that backarc shortening occurs at rates of ~4-5mm/yr over a zone that is ~30km wide (across-strike) (Brooks et al., 2003; Kendrick et al., 2006). In the north (31°- 32°10° S) this would imply that the west-vergent, Eastern Precordilleran structures are the most likely to be active, while south of 32°10° S the east-vergent structures in the Southern Precordillera belt are likely to be most active (Fig. 1).
I came across this great initiative after Richard Styron sent the announcement via the Geotectonics mailing list. He’s currently maintaining these projects. The idea is to compile all available data on active structures in the Himalaya using the GitHub infrastructure (basically a collaborative platform for programming) . Everyone can join and help compiling active faults in this region. The data is then available to everyone for free in different data formats. The same thing is currently happening for the Andes region, too! more
Today we went for field work again – mapping active faults in Northern Attica, trying to find out about offsets and slip rates, and scouting sites for applying Ground Penetrating Radar (GPR) later. We found some very beautiful fault scarps and measured a good number of strike and dip values. At two locations we also recorded topographic profiles across the scarps in order to get an idea about the vertical offset. Combined with the assumption that these scarps are post-glacial, we can estimate slip rates. more
I am currently in Greece for field work on faults in the vicinity of Athens. Sascha from RWTH Aachen University is doing his MSc. thesis on remote sensing, geophysical analyses, and mapping of some structures that we think could be active, and me and Ioannis are with him in the field for the first few days. Right on the first day we found some promising outcrops which we will map and check in detail during the next days. more