High Resolution Imaging of the Geometry and Seismic Properties of the Karadere-Duzce Branch of the North Anotolian Fault at Depth

University Of Southern California, Los Angeles CA

Investigators

Abstract

Abstract for proposal EAR0003401 (PH # 41x) Title: High Resolution Imaging of the Geometry and Seismic Properties of the Karadere-Duzce Branch of the North Anatolian Fault at Depth PI's: Y. Ben-Zion and D. Okaya, University of Southern California This research will conduct a comprehensive high resolution imaging of the Karadere-Duzce branch of the North Anatolia Fault, using near-fault seismic data collected along and around the Karadere-Duzce rupture zone during the 5.5 months following the Mw7.4 August 17, 1999, earthquake by a RAMP PASSCAL seismic network. The study area straddles the structurally important eastern and western ends of the August 17 and November 12, 1999, M 7+ ruptures. Research will include analysis, interpretation, and integration of information from the following categories of studies: (1) regional imaging using earthquake travel time tomography; (2) several possible seismic signatures of damaged fault zone material at depth including anisotropy, non-linear wave propagation, and fault zone trapped and head waves effects; and (3) high-resolution hypocenter locations of recorded seismicity. Goals of the research are: 1) providing high resolution imaging of width, continuity, and seismic properties of the fault zone at depth; and 2) establishing correlations between (a) lithology and fault offsets at the surface, (b) space-time patterns of large earthquake ruptures, (c) microseismicity patterns at depth, and (d) properties of damaged fault zone rock at depth as imaged by various seismic signals. Results of the research will contribute to a better understanding of properties and mechanics of major transform plate-boundary fault zones. The developed integrated methodology will be useful for applications to other fault systems.