Facility Support: The Global CMT Project

Columbia University, New York NY

Investigators

Abstract

0824694 Ekstrom This proposal seeks funding to continue the Centroid-Moment-Tensor (CMT) Project. This facility represents a 25-year-long endeavor to catalog, analyze, and maintain data on global earthquake activity and focal mechanisms. Global, comprehensive seismic strain relief records are maintained and made available through the CMT project. The cataloging began in 1976 with the initial goal of analyzing moment tensor and centroid location for all earthquakes with a magnitude greater or equal to 5.0. Currently, data are distributed within one day of occurrence. Current funding is solicited to maintain and upgrade to better and more modern methods of information dissemination. Global and regional tectonic activity and associated processes can be modeled, interpreted, constrained, and better understood thought CMT analysis. Tomographic research also benefits from CMT analysis. Overall, five specific activities are identified, 1) determine and archive moment tensors for greater than magnitude 5.0 earthquakes with global coverage, 2) rapidly identify and determine moment tensors for earthquakes with M>5.5 and quickly disseminate results, 3) curate and maintain the CMT catalog and develop improvements to distribute data more effectively, 4) event detection for seismic sources from surface waves and cataloging/distributing the data, and 5) determining waveform quality from the GSN and other seismic networks. The PIs each request one month salary and funding is sought for two half-time research assistants. PIs will maintain and monitor software, data acquisition protocols and data workflow and supervise research assistants. The CMT data archive and rapid CMT results from major seismic events have been highly recognized throughout the community. CMT magnitude estimates are distributed and considered ?authoritative? by the USGS. The catalog is considered the standard and localized earthquake studies rely on these data as a starting point. CMT data is widely used by tomographers needing to create synthetic seismograms. CMT data, besides uses in research, is widely applied for educational purposes. ***