Almaty sits on a huge active fault, and here is why we know

Almaty, the former capital of Kazakhstan and home to ~2 million people, is a rapidly growing, vibrant city, beautifully situated at the foothills of the mighty Zailisky Alatau, the northernmost mountain range of the Tien Shan at this longitude. The city sits on a huge alluvial fan with the snow-capped mountains in the background, reaching 5,000 m elevation. Almaty has suffered from earthquakes in its young history: in 1887, the Verny earthquake with a magnitude of about 7.3 had its epicentre a few kilometres west of the city but did not produce surface ruptures (Verny is the old name of Almaty). Only two years later, the M8 Chilik earthquake ruptured the surface 100 km to the southeast of Almaty. Finally, Almaty was heavily damaged by the 1911 Chon Kemin earthquake with a magnitude of ~8, which occurred on the southern flank of the Zailisky Alatau. In our new paper we now report on a fault that did not rupture in historical times, but surely did so in the Holocene – and this fault is right beneath the city. Continue reading “Almaty sits on a huge active fault, and here is why we know”

New papers on paleoseismology, active tectonics and tsunami research

Pissia Fault scarp

Several new papers deal with paleoseismology and active tectonics studies. Wiatr et al. used terrestrial LiDAR to analyse limestone bedrock scarps, Hornblow et al. investigated the Darfield earthquake source in NZ. Sarikaya et al. present new data on offset alluvial fans in Central Turkey; Xu et al. present geological data on two historical seismic events in Tibet. Tectonic morphology is used by Barcelona et al. in NW Argentina. Mathew et al. use remote sensing data to analyze coseismic deformation in China. Ed Garrett and colleagues present data on 1000 years of megathrust quakes in Chile, and Bemis et al. have an interesting article on UAVs and paleoseismology. Continue reading “New papers on paleoseismology, active tectonics and tsunami research”

New paper: Wiatr et al., 2013 – Slip vector analysis with high resolution t-LiDAR scanning

A new paper in Tectonophysics deals with the use of terrestrial LiDAR for identifying the slip vectors on fault planes. Thomas Wiatr, Klaus Reicherter, Ioannis Papanikolaou, Tomás Fernandez-Steeger and Jack Mason collected and processed data from Crete island (Greece), where they scanned the scarp of the Spili Fault. They imaged numerous kinematic (slip direction) indicators like slickensides with this relatively new technique. The t-LiDAR data were then compared to traditional compass measurements in order to get an idea about the derivation betwen old-school measurements and high-tech methods.  Continue reading “New paper: Wiatr et al., 2013 – Slip vector analysis with high resolution t-LiDAR scanning”