This electronic supplement contains the earthquake catalog used in our study of triggered seismicity from the Denali Fault Earthquake (DFE). This catalog includes 2,651 earthquakes which occurred during the time period January 1, 2000, through June 30, 2003, within a rectangular region we refer to in the paper as the "Utah Region": 36° 45´ N to 42° 30´ N, 108° 45´ W to 114° 15´ W. The catalog was extracted from the earthquake bulletins for the Utah region, routinely published by the University of Utah Seismograph Stations (UUSS) each quarter (see http://quake.utah.edu/catalog/quarterly.shtml ). As described in the paper, a major effort was made to improve the completeness of the catalog during the first few hours after the DFE when the DFE surface waves interfered with the normal UUSS data processing. Quarry blasts have been removed from the catalog based on location, time of day, and information provided by the quarry operators. We have also removed all seismic events from areas in east-central Utah dominated by mining-related seismicity (see Arabasz et al., 1997, 2002).

A brief overview of routine data processing at the University of Utah Seismograph Stations follows. The reader is directed to Nava et al. (1990) and Arabasz et al. (2002, 2003) for more detailed descriptions of UUSS data acquisition and processing procedures.

The routine network data processing during the time period covered by the catalog utilized data from time windows containing potential seismic events identified by the triggering algorithm of Johnson (1979). P- and S-wave arrival times were picked for local seismic events found in these time windows and used to compute hypocentral locations with a modified version of the computer program Hypoinverse (Klein, 1978) and a set of three region-specific velocity models (see Nava et al., 1990). If possible, local magnitude (M_L) was computed from maximum peak-to-peak amplitudes on paper or synthetic Wood-Anderson seismograms-the latter created primarily from UUSS and U.S. National Seismic Network broadband digital telemetry data. Coda magnitude (M_c), a calibrated estimate of M_L, was computed for most of the earthquakes using gain-corrected measurements of seismic signal durations on short-period, vertical-component velocity sensors (Pechmann et al., 2001; Arabasz et al., 2003). These signal duration measurements were made with the aid of UUSS-developed software which fits an equation to the latter part of the seismic record where the amplitude decays with time. Magnitude measurements for some of the local earthquakes whose waveforms were superimposed on the DFE surface waves were made on filtered records, as discussed in the paper. The preferred magnitude is M_L when M_L values from two or more stations are available to be averaged. Magnitudes were determined for 99.5% of the events. For most of the remainder, the reason that magnitudes could not be determined was interference from the DFE surface waves or from other local earthquakes.

The listing of earthquakes in the Utah DFE-Triggering Study Catalog is in modified Hypo71 summary output format:
 

References

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