Interactive World Wide Web Page for Custom Event Screening at the PrototypeInternational Data Center

摘要

This report describes statistical event characterization tools and related dataproducts being implemented at the Prototype International Data Center (PIDC) in Arlington, Virginia. Preliminary event screening analyses at the PIDC currently utilize seismic measures of location, depth, mb-Ms, and their uncertainties, as well as regional high-frequency amplitude ratios. To make these tools and data products accessible to remote users, interactive World Wide Web pages have been implemented for custom event screening. These Web pages provide a preliminary capability for users to select and analyze events based on event characterization parameters and user-defined screening criteria. A wide range of maps and other displays of the data and screening results are provided. These tools allow the user to process, view and download customized event characterization data products and graphics over the Internet. Two basic services are described: (1) an interactive event screening service which allows custom criteria to be provided and applied during an on-line session; and (2) a subscription service utilizing user-specified event screening criteria that remain in affect until they are changed by the user. Examples of how to access and use the Web pages, as well as applications to GSETT-3 data, are presented for the two types of services. A preliminary assessment of the event characterization capability at the PIDC, over time, is also presented. Results are described of an application to seismic events in Eurasia that occurred between 1 June and 31 July 1996. These events include two underground nuclear explosions at the Lop Nor test site in China and provide a useful test of the event screening tools.