Deformation due to the 17 August 1999 Izmit, Turkey, earthquake measured from SPOT images
نویسندگان
چکیده
[1] The geometry of the ruptured areas and the coseismic slip distribution data are key to highlighting the behavior of seismic faults. This information is generally retrieved from field investigations and geodetic measurements or synthetic aperture radar (SAR) interferometry. Here we show that SPOT images can also be used to accurately map the fault zone and to determine the slip distribution by subpixel correlation of images acquired before and after an earthquake. The measured slip includes the contribution of possible distributed shear that might not be clearly expressed in surface ruptures and smoothes out possible along-strike variability due to near-surface fault complexities. We apply the technique to the Ms = 7.4, 1999, Izmit earthquake. Our results reveal a <100-m-wide and very linear fault zone that can be traced for 70 km from Gölcük to Akyazi, along which supershear rupture has been inferred. The obtained slip distribution compares well with the field measurements and is consistent with ground deformation measured at some distance from the fault zone using SAR images. Very little deformation was accommodated off the main fault plane. Maximum slip is observed near Sapanca lake at a small fault jog that has probably influenced rupture propagation.
منابع مشابه
Coherence Tracking Measurements of the August 1999 Izmit Earthquake
The 17 of August 1999, an important earthquake of magnitude 7.6 occurred along the North Anatolian fault in the area of Izmit (Turkey). Relative horizontal displacements up to 4.5 meters were observed. The epicenter of the earthquake under concern is located in Golcuk, near the city of Izmit, on the South border of the Marmara Sea. The fault in the vicinity of Izmit is mainly oriented along an ...
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