Source and Path Calibration in Regions of Poor Crustal Propagation using Temporary, Large-Aperture, High-Resolution Seismic Arrays

摘要

Broadband seismic data acquired during the Hi-CLIMB field experiment are used to study seismic events and path propagation in the Nepal Himalaya and south-central Tibetan Plateau. Similarities in regional propagation between Tibet and Iran motivate this new study. The 2002-2005 Hi-CLIMB experiment consisted of 233 stations distributed along a dense 800 km linear north-south array extending from the Himalayan foreland into the central Tibetan Plateau. The main array was flanked by a 350 km x 350 km sub-array in southern Tibet and central and eastern Nepal. Our dataset provides an opportunity to obtain seismic event locations for ground truth (GT) evaluation, with Q emphasis on depth, to determine source parameters, and to study distance evolution of seismic coda for yield estimation in low Q regions. Event detection and preliminary automatic location analysis show tens of thousands, otherwise undetected, local seismic events. We will obtain high-quality event locations from manual P- and S-wave picks by joint inversion for location and 2D and 3D velocity structure. We will also perform relative locations to resolve spatial relations of several highly active event clusters. Besides GT-compatibility, high-quality locations are essential for the source parameter and coda evolution portions of the study.