Northern California Seismicity Report for the week ending May 24, 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

• 27 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 3.4, 11 miles NW of Alder Springs, CA at 06:57 PM UTC Tuesday, 05 22, 2001 (11:57 AM PDT Tuesday, May 22, 2001).

• 13 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 2.8, 5 miles WNW of San Juan Bautista, CA at 11:45 PM UTC Saturday, 05 19, 2001 (04:45 PM PDT Saturday, May 19, 2001).

• 8 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 2.8, 8 miles ESE of Mammoth Lakes, CA at 01:44 PM UTC Monday, 05 21, 2001 (06:44 AM PDT Monday, May 21, 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 MAY 17 0407 45.40 36 27.55 121  1.61  2.31 31 .07  .2  .6 BIT    2.0D  75  7 NN
2001 MAY 17 1043 17.60 39 33.33 123 21.66  8.78 21 .05  .1  .6 MAA    2.2D  83 11 NN
2001 MAY 18 1203 58.85 38 46.32 122 44.50  3.44 30 .06  .2  .4 GEY    2.2D  34  2 NN
2001 MAY 18 1332 17.91 38 49.70 122 48.04  4.64 41 .05  .1  .3 GEY    2.6D  32  2 NN
2001 MAY 19 1258 15.76 40 37.46 124 24.05  9.63 12 .04  .8  .4 EUR    2.2D 219 17 NN
 
2001 MAY 19 1722 54.77 37 38.68 119 24.67  1.62 32 .14  .4 6.1 KAI  # 2.1D  72 29 NN
2001 MAY 19 1918 29.30 37 38.55 119 23.21 13.49 34 .09  .3 1.4 KAI    2.1D  70 27 NN
2001 MAY 19 2153 21.38 40 29.52 124 24.39 25.77 16 .03  .6  .7 EUR    2.0D 218  6 NN
2001 MAY 19 2345 59.26 36 52.81 121 36.68  5.90 70 .10  .1  .3 SJB    2.8D  51  2 NN
2001 MAY 20 0532 48.70 38 49.57 122 47.01  1.13 12 .05  .2  .6 GEY    2.2D  52  2 WW
 
2001 MAY 21 0413 47.15 39 45.11 122 52.31  0.62 37 .46  .5 5.6 SAC    2.3D  47 17 NN
2001 MAY 21 0746 14.79 36 41.48 121 19.29  4.37 55 .05  .1  .2 STN    2.0D  42  3 NN
2001 MAY 21 1344 18.39 37 36.00 118 50.60  8.87 34 .07  .3  .4 SMO    2.8D  91  2 NN
2001 MAY 21 1710 33.25 37 17.11 119 56.54 19.49 10 .02  .3  .7 KAI    2.4D 118 19 NN
2001 MAY 21 2119 20.77 39 22.22 122 51.56 11.70 42 .10  .2  .5 BAR    2.8D  85 15 NN
 
2001 MAY 22 0035 54.00 36 40.50 121 17.83  4.77 63 .06  .1  .3 STN    2.7D  40  6 NN
2001 MAY 22 0125 29.49 36 40.54 121 17.87  5.05 64 .07  .1  .3 STN    3.2L  39  6 NN
2001 MAY 22 0210 47.13 36 40.70 121 18.05  4.12 38 .05  .2  .5 STN    2.0D  40  5 WW
2001 MAY 22 0253 26.37 37 38.70 119 24.68  2.86 42 .20  .4 3.9 KAI  # 2.1D  63 29 NN
2001 MAY 22 0727 28.23 39 45.39 122 51.36  0.94 44 .19  .2 3.7 SAC  # 2.9D  73 17 NN
 
2001 MAY 22 0748 18.34 39 45.59 122 51.31  0.44 46 .18  .2 1.1 SAC    3.1D  72 17 NN
2001 MAY 22 1857 46.08 39 45.75 122 51.72  0.42 40 .38  .4 2.6 SAC    3.4L  39 17 WW
2001 MAY 22 1912 33.19 39 45.72 122 51.63  4.01 17 .20  .515.9 SAC  - 2.3D  80 17 WW
2001 MAY 23 0500 32.50 36  5.00 120  9.68 12.51 37 .12  .2  .3 COA    2.6D  97  5 WW
2001 MAY 23 0500 58.98 36  5.47 120  8.58  9.04 14 .05  .5 1.4 COA    2.3D 161 25 WW
 
2001 MAY 23 1801 57.23 38 44.54 122 41.81  2.48 14 .07  .3  .7 NAP    2.2D  72  4 WW
2001 MAY 23 2001 53.95 35 45.91 121 15.22  1.29 14 .06  .4 2.0 SSM    2.3D 190 13 WW