TYPE: Both

PLANNING FOR AN ADVANCED NATIONAL SEISMIC SYSTEM IN THE CENTRAL

AND SOUTHEAST U.S.

Mitch Withers, withers@ceri.memphis.edu, and the ANSS-MA Regional Subcommittee.

As required by Public Law 105-47 the USGS undertook a review of the state of seismic monitoring in the US. A workshop was held in Colorado in the summer of 1998. Major seismic network operators and selected recipients of network products participated in this review. A report was drafted based on this workshop and published in USGS Circular 1188, "An Assessment of Seismic Monitoring in the United States." In addition to a review of the current monitoring status, this report provides recommendations for the modernization of seismic networks and their infrastructure. In the reauthorization act for the National Earthquake Hazard Reduction Program (NEHRP), Congress responded to the receipt of the report by requiring the USGS to provide them with a management and implementation plan for an "Advanced National Seismic Research and Monitoring System" (ANSS). At a one-day meeting in New Mexico this past February, representatives of a dozen different seismological organizations outlined such a management plan. An over-riding theme of this plan is that seismic monitoring of the US should be implemented within regions representing the major physiographic and tectonic parts of the country. No more than six to ten regions or groups should be so defined, one of which is a national group to provide linkages between the actual regions as well as to provide broad coverage of the whole US and include global monitoring. To this end, a Regional Subcommittee has been established for the Mid-America region (ANSS-MA) and the Mid-America Earthquake Center (MAEC) has earmarked funds to support production of a management and implementation plan. We present a draft of this plan for community comment and critique. Additional information on ANSS-MA is available via a temporary url: www.ceri.memphis.edu/CUSSN.