Seismicity Rates for 2002 Seismic Hazard Maps

Central and Eastern U.S. seismicity grid (CEUSagrid1008.asc), 4.5 Mb
dmag= 0.1, rate per year per cell for earthquakes between mblg magnitude -0.05 and +0.05, using b-value grid given below. Each cell is centered at the given latitude and longitude.

Central and Eastern U.S. b-value grid (CEUSbgrid.asc), 4.1 Mb
For most of CEUS b=0.95, for Charlevoix region b=0.76. When b-value in file is listed as zero in the file, the b-value is set to 0.95.

California seismicity grid (CAagrid927.asc), 1.9 Mb
dmag= 0.1, rate per year per cell for earthquakes with moment magnitude between -0.05 and +0.05, using a b-value of 0.8. Does not include eastern California, the creeping section of the San Andreas fault, the Brawley zone, or earthquakes in northern California deeper than 35 km.

Seismicity grid for creeping section of San Andreas fault (creepagrid927.asc), 1.8 Mb
dmag=0.1, rate per year per cell for earthquakes with moment magnitude between -0.05 and +0.05, using b-value of 0.9. This grid is derived from azimuthal smoothing of seismicity.

Seismicity grid for Brawley zone of southern California (brawagrid927.asc), 1.8 Mb
dmag=0.1, rate per year per cell for earthquakes with moment magnitude between -0.05 and +0.05, using b-value of 0.8. This grid is derived from azimuthal smoothing of seismicity.

Seismicity grid for extensional area of western U.S. (EXTagrid927.asc), 2.0 Mb
including eastern California, dmag=0.1, rate per year per cell for earthquakes with moment magnitude between -0.05 and +0.05, using b-value of 0.8.

Seismicity grid for non-extensional area of western U.S., excluding California, (WUSagrid927.asc), 1.9 Mb
dmag= 0.1, rate per year per cell for earthquakes with moment magnitude between -0.05 and +0.05, using b-value of 0.8. Does not include earthquakes deeper than 35 km.

Seismicity grid for deep earthquakes (cadeepagrid927.asc), 1.8 Mb
(depth > 35 km) in northern California, dmag=0.1, rate per year per cell for earthquakes with moment magnitude between -0.05 and +0.05, using b-value of 0.8.

Seismicity grid for deep earthquakes (pacnwdeepagrid927.asc), 1.8 Mb
(depth > 35 km) in the Puget Sound region, dmag=0.1, rate per year per cell for earthquakes with moment magnitude between -0.05 and +0.05, using b-value of 0.4.

These files are also available via Anonymous FTP