InSAR analysis of the 2000 - 2002 earthquake sequence along the Sultan Dag front in the Isparta Angle (southern Turkey)
Abstract
The Sultan Dag range of southern Turkey is a fault-block mountain range that has developed within or at the edge of the Isparta Angle - a region of the Anatolian plate situated near a tear in the subducting slab of the African plate. The mountain range is bounded on the northeast by the Sultandagi-Aksehir fault and the Aksehir-Afyon graben. A sequence of moderate earthquakes that occurred between 2000 and 2002 provides insight into the incremental growth of the mountain front through individual seismic events. The earthquake sequence consists of three moderate size events: a Mw 5.1 and a Mw 6.0 earthquake (December 15, 2000) and a Mw 6.5 earthquake (February 3, 2002). Surface deformations corresponding with the individual earthquakes were imaged using Interferometric Synthetic Aperture Radar (InSAR). The resulting displacement maps were used with elastic dislocation models to estimate faulting parameters associated with each earthquake (fault orientation and slip). These fault models were subsequently used to estimate static coulomb stress changes resulting from the earthquakes. The findings suggest that the two events of December 15, 2000, were not directly related to one another in terms of stress triggering. However, both events from 2000 appear to influence the extent of the 2002 earthquake. The larger event increased the stress on the segment ruptured in 2002, whereas the stress shadow from smaller event, which occurred on an antithetic fault, appears to have unloaded the stress at the termination of the 2002 rupture. Furthermore, the uplift and subsidence patterns associated with the earthquakes closely mimic overall geologic structure and general topography. Hence, these results permit exploring the extrapolation of coseismic displacements to understand the long-term growth of the mountain front.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2009
- Bibcode:
- 2009AGUFM.T53G..07M
- Keywords:
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- 1240 GEODESY AND GRAVITY / Satellite geodesy: results;
- 7230 SEISMOLOGY / Seismicity and tectonics;
- 8107 TECTONOPHYSICS / Continental neotectonics