Northern California Seismicity Report for the week ending May 31, 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

• 19 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, 2 miles NNW of Pinnacles National Monument, CA at 10:54 PM UTC Saturday, 05 26, 2001 (03:54 PM PDT Saturday, May 26, 2001).

• 12 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 2.5, 8 miles N of Morgan Hill, CA at 01:18 PM UTC Tuesday, 05 29, 2001 (06:18 AM PDT Tuesday, May 29, 2001).

• 23 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 2.9, 8 miles SE of Mammoth Lakes, CA at 11:46 AM UTC Thursday, 05 24, 2001 (04:46 AM PDT Thursday, May 24, 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 24 0444 37.30 37 34.43 118 52.10  5.28 32 .06  .2  .4 MOR    2.1D 101  4 NN
2001 MAY 24 1146 47.37 37 34.34 118 52.16  5.11 35 .07  .2  .4 MOR    2.9D 101  4 NN
2001 MAY 24 1717 47.07 37 34.46 118 52.09  5.49 26 .06  .3  .5 MOR    2.2D 100  4 WW
2001 MAY 24 2025 56.66 37 34.41 118 52.18  4.64 27 .08  .3  .6 MOR    2.2D 101  4 WW
2001 MAY 25 1559 20.41 36 14.81 120 48.41  8.66 30 .05  .3  .6 BIT    2.2D  79 14 WW
 
2001 MAY 26 0335  0.58 36 11.61 120 46.13  7.85 23 .09  .2  .5 BIT    2.1D  88  4 WW
2001 MAY 26 2254 22.86 36 33.88 121  9.18  4.78 62 .07  .1  .5 PIN    3.2L  38  8 WW
2001 MAY 27 0028 14.10 36 37.22 121 13.55  5.07 32 .05  .2  .8 PIN    2.1D  56  7 WW
2001 MAY 27 1911 55.26 37 33.93 118 37.76 11.38 10 .03  .4 1.5 CAS    2.0D  68  7 NN
2001 MAY 28 0634  7.47 40 34.03 122 24.80 24.03  8 .34 1.729.3 SHA  - 2.2D 150 40 WW
 
2001 MAY 28 0809 30.11 35 29.22 120 46.95  4.84 14 .02  .4  .9 SSM    2.1D 132 12 WW
2001 MAY 29 0915 22.72 36 40.70 121 18.20  4.99 53 .06  .1  .4 STN    2.6D  35  5 WW
2001 MAY 29 1036  0.69 36 47.10 121 25.76 10.44 32 .09  .2  .4 SJB    2.1D  70  4 WW
2001 MAY 29 1112 59.32 39 45.93 122 51.65  0.99 29 .20  .3 6.4 SAC  # 2.9D  44 18 WW
2001 MAY 29 1312 36.85 37 14.86 121 38.13  5.08 74 .05  .1  .4 SFL    2.4D  57  4 WW
 
2001 MAY 29 1318 39.80 37 14.90 121 38.17  4.81 74 .06  .1  .4 SFL    2.5D  57  4 WW
2001 MAY 29 1826 31.55 37 28.79 118 50.34  5.23 22 .07  .3  .8 MOR    2.0D 128  8 WW
2001 MAY 30 1047 26.31 35 25.20 120 42.43  5.06 21 .09  .2  .5 SSM    2.2D  71  3 WW
2001 MAY 30 2033  0.25 38 54.71 122 33.76  5.32 14 .07  .5 1.4 BAR    2.3D 176 10 WW