Northern California Seismicity Report for the week ending Aug 08, 2002

This report provides a brief summary of earthquake activity recorded by the U.S. Geological Survey Northern California Seismic Network in Menlo Park and the University of California Berkeley Seismological Laboratory. It is automatically generated each Wednesday shortly after midnight, Universal time (UT). UT (ie., Greenwich Mean Time) is 8 hours ahead of PST or 7 hours ahead of PDT.

Because it is not possible to review all of the earthquakes before this report is generated, it may contain errors. Please report errors or provide suggestions and comments to ncsn@andreas.wr.usgs.gov

The report no longer includes maps showing earthquakes for the entire US or world. Those maps are now available from the U.S.G.S. National Earthquake Information Center. In addition, all earthquake data can be retrieved from the Northern California Earthquake Data Center.

Please note that some of the earthquake data in this report have been reviewed by seismic analysts. Consequently, the parameters that describe the hypocenter, magnitude, origin time, and solution statistics may differ slightly from the information contained on the real-time earthquake web page. The differences reflect revised arrival times at seismic stations and the analysts' decisions to include or exclude information from seismic stations.

The minimum magnitude ( M) values in the following bullets reflect the smallest earthquake which the network can routinely record within the region. During the previous seven-day period ending at midnight (UT) Wednesday, our seismic networks recorded

• 20 M >2.0 earthquakes in Northern and Central California (map) (within dashed polygon of figure).

The largest event to occur this week in this region was a minor earthquake of magnitude 3.2, 3 miles NE of The Geysers, CA at 09:45 PM UTC Sunday, 08 04, 2002 (02:45 PM PDT Sunday, Aug 04, 2002).

• 9 M >1.2 earthquakes in the San Francisco Bay area (map).

The largest event to occur this week in this region was a microearthquake of magnitude 2.3, 2 miles SW of San Juan Bautista, CA at 06:59 PM UTC Monday, 08 05, 2002 (11:59 AM PDT Monday, Aug 05, 2002).

• 8 M >1.2 earthquakes in the Long Valley region (map).

The largest event to occur this week in this region was an earthquake of magnitude 1.9, 8 miles WSW of Toms Place, CA at 04:35 PM UTC Saturday, 08 03, 2002 (09:35 AM PDT Saturday, Aug 03, 2002).

The following table provides a listing of all M >2 earthquakes that occurred this week. An explanation of the entries in the table is available.

---ORIGIN TIME (UT)--- -LAT N-- --LON W-- DEPTH  N RMS ERH ERZ LOC    PREF AZ MIN S. PAGE   1
YEAR MON DA HRMN  SEC  DEG MIN  DEG  MIN    KM  RD SEC  KM  KM REMKS  MAG  GAP DS PF

2002 AUG  1 2306 20.04 38 49.35 122 46.05  3.49 30 .05  .1  .4 GEY    2.1D  48  3 NN
2002 AUG  2 0323 42.56 38 44.92 122 43.12  1.99 23 .07  .2  .4 NAP    2.3D  51  3 NN
2002 AUG  2 0500 11.14 36  0.28 120 33.64  5.38 41 .06  .2  .2 SLA    2.4D  76  5 NN
2002 AUG  3 0108 51.16 40 49.48 123 46.37 27.62 13 .05  .3  .6 EUR    3.0D 115  7 AN
2002 AUG  3 0131 54.49 35 53.68 120 26.02 10.98 24 .03  .3  .3 GOL    2.1D 110  3 WW
 
2002 AUG  3 0231 26.29 40 18.63 123 15.14 32.72 18 .07  .3  .9 KLA    2.1D  53 10 AN
2002 AUG  3 2235  6.45 40  8.60 123 51.16 23.17 29 .12  .3  .4 MEN    2.9D 114  6 NN
2002 AUG  4 0124  6.40 40  8.94 123 50.67 22.62 18 .09  .3  .4 MEN    2.1D 123  5 AN
2002 AUG  4 0907 41.07 36  0.14 120 33.04 11.04 44 .04  .2  .2 SLA    2.2D  52  6 NN
2002 AUG  4 0912 42.39 40 24.36 124  5.56 22.62  8 .09  .7  .6 MEN    2.5D  90  3 WW
 
2002 AUG  4 1406 21.98 38 49.40 122 46.12  2.10 16 .06  .2  .6 GEY    2.0D  47  3 WW
2002 AUG  4 2127 32.29 39 58.03 122 23.36 24.35 10 .06 1.0  .6 SAC    2.0D 124 19 AN
2002 AUG  4 2145  7.35 38 49.53 122 45.80  3.97 39 .07  .1  .3 GEY    3.2L  49  3 NN
2002 AUG  4 2154 17.74 38 44.75 122 42.94  2.82 24 .05  .2  .3 NAP    2.1D  53  3 NN
2002 AUG  5 0323 52.85 35 56.18 120 40.39 12.44 41 .07  .2  .4 ROB    2.0D  38  7 NN
 
2002 AUG  5 0502  6.04 38 45.26 122 44.33  2.69 31 .07  .2  .5 GEY    2.8D  37  3 WW
2002 AUG  5 0641 32.92 35 56.24 120 40.47 12.39 52 .07  .2  .4 ROB    3.1L  38  7 NN
2002 AUG  5 0723  9.85 35 56.10 120 40.45 12.68 44 .05  .2  .4 ROB    2.5D  38  7 NN
2002 AUG  5 1859 43.38 36 49.84 121 33.67  7.24 59 .08  .1  .2 SJB    2.3D  40  2 NN
2002 AUG  7 1403 46.18 38 47.87 122 46.75  1.13 30 .06  .2  .4 GEY    2.6D  39  2 WW