Northern California Seismicity Report for the week ending Aug 02, 2001

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

• 24 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 microearthquake of magnitude 2.7, 13 miles N of Angwin, CA at 04:21 AM UTC Tuesday, 07 31, 2001 (09:21 PM PDT Monday, Jul 30, 2001).

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

The largest event to occur this week in this region was an earthquake of magnitude 2.4, 2 miles ESE of San Ramon, CA at 05:28 PM UTC Friday, 07 27, 2001 (10:28 AM PDT Friday, Jul 27, 2001).

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

The largest event to occur this week in this region was a microearthquake of magnitude 2.2, 7 miles W of Toms Place, CA at 12:27 AM UTC Thursday, 07 26, 2001 (05:27 PM PDT Wednesday, Jul 25, 2001).

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

2001 JUL 26 0027 37.17 37 32.98 118 47.98  8.90 30 .05  .2  .6 MOR    2.2D 106  3 WW
2001 JUL 26 0425 54.96 36 33.27 121  8.12  8.59 42 .05  .1  .3 PIN    2.4D  36  5 NN
2001 JUL 27 0044 45.62 40 37.09 123 56.06 22.16 13 .02  .3  .5 EUR    2.1D 145 23 NN
2001 JUL 27 0823 24.48 38 48.87 122 48.24  1.22 16 .01  .2  .3 GEY    2.0D  41  1 NN
2001 JUL 27 1437 42.64 37 56.23 122  5.30 11.00 49 .17  .2  .3 CON    2.1D  77  2 NN
 
2001 JUL 27 1704  0.87 40 13.63 123 14.95 31.86 13 .07  .4 1.5 KLA    2.4D 105 16 WW
2001 JUL 27 1723 19.16 37 46.68 121 57.13  7.73 12 .14  .4 1.0 DAN    2.3D  96 11 WW
2001 JUL 27 1728 35.52 37 46.33 121 56.65 10.26 70 .11  .2  .3 DAN    2.4D  63 11 NN
2001 JUL 28 0542 32.29 39 10.79 122 40.73  5.20  9 .30 1.9 2.9 BAR    2.6D 139 16 WW
2001 JUL 28 1111 26.71 40 34.91 122  8.32 17.58 12 .06  .4 1.0 SHA    2.2D 117 17 WW
 
2001 JUL 29 1705 39.08 38 47.63 122 44.78  0.02 13 .04  .2  .7 GEY  # 2.4D  89  3 WW
2001 JUL 29 1921 12.62 36 42.21 121 20.11  2.68 43 .08  .2  .3 STN    2.2D  52  1 WW
2001 JUL 29 1952 17.01 36 30.22 120 28.44 11.99 14 .19  .8 2.1 CRV    2.2D 116 21 WW
2001 JUL 30 0110 36.88 39 36.47 122 49.08  0.03 17 .20  .5 2.1 SAC  # 2.3D  55 10 WW
2001 JUL 30 0244 13.88 38 40.88 122 47.69  5.51 28 .10  .2  .6 NAP    2.5D  87  5 WW
 
2001 JUL 30 0639 19.79 38 51.41 122 51.37  2.02 24 .06  .2  .4 GEY    2.4D  45  2 WW
2001 JUL 30 1631 39.09 38 49.24 122 48.06  4.60 32 .06  .2  .4 GEY    2.7D  35  2 WW
2001 JUL 30 1837 34.09 38 49.40 122 47.07  1.26 17 .05  .2  .4 GEY    2.1D  53  2 WW
2001 JUL 31 0421 32.54 38 45.75 122 26.14  9.41 38 .15  .2  .6 GVL    2.7D  78  5 WW
2001 JUL 31 0654 33.52 36 13.60 120 48.19  8.13 33 .11  .3  .7 BIT    2.2D  88 15 WW
 
2001 AUG  1 1530 41.14 36 12.89 120 47.28  7.60 34 .14  .2  .7 BIT    2.2D  93 13 WW
2001 AUG  1 1732 28.85 36 42.22 121 20.31  4.75 43 .05  .2  .4 STN    2.2D  52  1 WW
2001 AUG  1 1821 53.58 39 48.14 123 35.58  3.86 16 .04  .3  .8 MAA    2.3D 127 10 WW
2001 AUG  1 2337 38.24 39 37.06 122 48.32  4.90 23 .15  .3 2.1 SAC    2.6D  48  9 WW