Space and Time Evolution of the Rupture for the 2010 August 27 Mw 5.8 Kuh-zar earthquake

Document Type : Research Paper

Authors

1 Physics Department, Zanjan University, Zanjan, Iran

2 Institute of Geophysics, University of Tehran, Tehran, Iran

Abstract

This study investigated the spatiotemporal slip distribution of the 2010 August 27 Mw 5.8 Kuh-zar earthquake. Using the constrained non-negative least-squares linear slip inversion method, we calculated the amount of displacement on the fault plane. The spatial slip distribution of this earthquake has been estimated by Bazargan et al. (2018), while the delta is 0.1 s ( delta is sampling rate means10 samples in 1 second). Here, we re-evaluated the slip with delta = 0.2 s to improve their result. A great many inversions were carried to determine the optimal parameters used in the process such as rupture velocity and rise time. In this study, we used the same rupture velocity and rise time, namely 2.55 km/s and 1.8 s. In general, the rupture velocity is 80% to 90% of the shear wave velocity, except for the propagation of ultrasonic faults, in which it has dimensions equal to the P-wave velocity. Selecting the size of the rupture rate has a significant effect on the size of the slip and its area. Since the slip inversion results can have a high level of uncertainty, we tried to develop the previous results by using different delta and adding time evolution to the calculations. The spatiotemporal slip distribution of this event got a data fit of 48% with an 8 cm peak slip.

Keywords


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