Converts data from EVT to SAC format

Extracts seismic data from CD-ROMs distributed by the National Earthquake Information Center (NEIC) of the United States Geological Survey (USGS) and converts it to a form compatible with the Lawrence Livermore National Laboratory Seismic Analysis Code (SAC).

The National Earthquake Information Center distributes event waveforms on CD-ROMS. The evt2sac program extracts the waveforms and converts them to SAC format. A profile specifies the parameters used by the program. The user can specify the time of the event of interest and also specify range and lag time to extract only records of interest. In addition, it is possible to specify that the program extract data around the arrival time of a phase. For example, one could specify that the data should extend from one minute before the arrival of the P wave and run until five minutes after the arrival of the S wave. The phases supported are P, S, pP, sS, PP, SS and surface waves. When specifying surface waves, the user can provide a surface wave group velocity window.

Alan Jones