Location Improvements in East Asia: Tomographic Model Analysis and Utilizing Public Data for Ground Truth Identification

摘要

We continue to collect seismic catalog data from various sources and search that data for possible information to improve regional location in East Asia. Data collection and search efforts have greatly increased the availability of ground truth (GT) events and improved our ability to create detailed tomographic models for the area. We have developed several regional phase tomography models for East Asia (see Rowe et al., 2008, these Proceedings) that display significant reduction in travel time residuals over starting models. Further analyses of these models are required to assess how such models will affect location accuracy and methods. We will determine how the tomography models reduce the travel time residuals for various stations within East Asia and what residual patterns remain after modeling. This will indicate whether any further location improvement can be expected by adding travel time correction surfaces to relocation methods in the area. GT is usually collected through analysis of seismic, infrasound and satellite data or through direct on-site access. GT for areas where information is limited or denied must be derived from alternative sources. We obtained accurate and precise locations of two chemical explosions detonated in December 2007 in northern China through analysis of public information from the Internet and Google Earth(Trademark).