Modification of Specific Barrier Model Using New Time Functions for Inclined Fault

Document Type : Seismology and Engineering Seismology

Authors

Tarbiat Modares University

Abstract

In the specific barrier model (SBM) as an earthquake source model, fault is assumed as a rectangle whose surface is covered by an aggregate of circular cracks of equal diameter (primary version) on which a local stress drop takes place to simulate high-frequency movements. Seismic moment in the SBM is computed in a deterministic manner on the fault plane, on the basis of moment and area constraints. In the SBM, rupture on cracks causes a stress drop that moves within circular cracks, and rupture tip sweeps the fault plane. In this paper, new time functions for inclined faults have been developed. The mentioned time functions have been obtained by using probability density functions (PDFs) of arrival time based on site positions, fault geometry and fault rotation angle. Finally, to calculate source spectra, PDFs of sub-events' size are assumed to be fractal. Various parameter studies are then conducted to show different features of the proposed PDFs on the results of the SBM.

Keywords


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