Northern California Seismicity Report for the week ending May 03, 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

• 33 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 light earthquake of magnitude 4.1, 18 miles WNW of Punta Gorda, CA at 04:55 AM UTC Wednesday, 05 02, 2001 (09:55 PM PDT Tuesday, May 01, 2001).

• 8 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 2.7, 7 miles WSW of Patterson, CA at 08:41 PM UTC Monday, 04 30, 2001 (01:41 PM PDT Monday, Apr 30, 2001).

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

The largest event to occur this week in this region was a minor earthquake of magnitude 3.1, 10 miles WSW of Toms Place, CA at 08:35 AM UTC Saturday, 04 28, 2001 (01:35 AM PDT Saturday, Apr 28, 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 APR 26 0452 11.79 38 49.89 122 45.26  1.58 43 .07  .1  .3 GEY    2.6D  51  4 NN
2001 APR 26 0508 28.82 36  1.92 119 55.53  5.91 41 .12  .7  .5 COA    2.4D 198 19 NN
2001 APR 26 0513 33.67 36 36.30 121 10.61  6.78 48 .06  .1  .4 PIN    2.2D  48  7 NN
2001 APR 26 0532 19.14 38 45.64 122 42.21  3.38 19 .06  .2  .5 GEY    2.1D  61  2 WW
2001 APR 26 0737 43.37 38 47.72 122 55.83  2.97 36 .07  .1  .7 GEY    2.4D  33  6 NN
 
2001 APR 26 0905 57.07 36  0.55 119 57.04  7.27 36 .18  .5  .6 COA    2.6D 190 15 NN
2001 APR 26 1121 40.35 36  0.59 119 57.48  5.48 29 .16  .6 1.0 COA    2.4D 202 16 NN
2001 APR 26 1121 51.52 35 58.87 119 57.22 11.97 14 .17 1.9 7.1 COA    2.4D 111 34 WW
2001 APR 26 1517  4.78 38 49.29 122 47.85  4.07 18 .05  .2  .5 GEY    2.0D  44  2 WW
2001 APR 27 0430 47.52 41  3.06 124 16.71 28.42  9 .04 2.1 1.0 EUR    2.3D 231 24 NN
 
2001 APR 27 1218  4.04 35 53.01 120 25.49  6.32 49 .05  .1  .2 GOL    2.9D  40  2 NN
2001 APR 28 0354 22.85 39 31.61 123  2.22  3.16 34 .09  .2 1.2 BAR    3.1L  48 10 NN
2001 APR 28 0554 26.61 35 27.84 120 46.20  3.33 47 .07  .2 1.0 SSM    2.7D  77 10 NN
2001 APR 28 0729 18.77 38 46.90 122 46.35  2.87 23 .05  .2  .6 GEY    2.2D  41  3 WW
2001 APR 28 0835 40.35 37 29.04 118 50.57  4.89 34 .07  .3 1.0 MOR    3.1D 127 11 NN
 
2001 APR 28 1316 17.36 37 28.82 118 50.63  4.18 31 .07  .3 1.1 MOR    2.2D 130 11 WW
2001 APR 28 2047 20.70 38 49.16 122 47.96  0.68 22 .05  .1  .3 GEY    2.1D  36  1 NN
2001 APR 29 2247 49.70 38 43.09 122 26.11  6.16 42 .19  .2  .7 GVL    2.1D  43  8 NN
2001 APR 30 0245  1.33 37 25.53 121 14.72  4.80 95 .21  .2  .7 JQN    2.4D  59 27 NN
2001 APR 30 0408 23.21 37 29.20 118 50.50  5.80 32 .06  .3  .7 MOR    2.5D 125  4 NN
 
2001 APR 30 1651 16.95 36 52.17 120 58.89  6.47 43 .14  .2 1.4 ORT    2.1D  92 14 NN
2001 APR 30 2041 38.03 37 25.02 121 14.50  6.33 89 .26  .3  .8 JQN    2.7D  42 27 WW
2001 APR 30 2304 45.23 38 49.36 122 48.10  4.46 20 .05  .2  .4 GEY    2.1D  41  2 WW
2001 APR 30 2305 15.82 37 35.37 118 47.62  7.35 30 .07  .3  .6 MOR    3.0D  97  3 WW
2001 MAY  1 0305 12.21 36 42.21 121 20.23  2.66 29 .07  .2  .3 STN    2.1D  52  1 WW
 
2001 MAY  1 1357 45.99 36 39.51 121 16.49  3.50 41 .07  .1  .6 STN    2.4D  57  6 WW
2001 MAY  2 0446 37.85 36 39.52 121 16.56  3.44 29 .07  .2  .7 STN    2.0D  56  6 WW
2001 MAY  2 0455 53.78 40 19.70 124 41.89 14.79 37 .08  .8  .6 MEN    4.1L 235 34 WW
2001 MAY  2 0703 59.92 38 47.12 122 43.20  3.04 27 .07  .2  .5 GEY    2.6D  39  1 WW
2001 MAY  2 0758 39.32 38 46.33 122 44.53  2.79 19 .06  .2  .5 GEY    2.1D  35  2 WW
 
2001 MAY  2 1340 53.65 37 37.03 118 51.71  4.66 27 .08  .3  .4 SMO    2.5D  88  1 WW
2001 MAY  2 1816 56.41 37 29.64 118 50.21  5.19 31 .06  .3  .9 MOR    2.0D 123 10 WW
2001 MAY  2 1821 15.80 38 40.45 122 45.90  5.51 21 .07  .2  .7 NAP    2.2D  40  4 WW