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@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
The largest event to occur this week in this region was a microearthquake of magnitude 2.8, 4 miles NE of Petrolia, CA at 01:32 PM UTC Saturday, 02 05, 2000 (05:32 AM PST Saturday, Feb 05, 2000).
The largest event to occur this week in this region was a microearthquake of magnitude 1.8, 7 miles SSE of Livermore, CA at 04:00 AM UTC Friday, 02 04, 2000 (08:00 PM PST Thursday, Feb 03, 2000).
The largest event to occur this week in this region was a microearthquake of magnitude 2.0, 8 miles W of Toms Place, CA at 10:33 PM UTC Sunday, 02 06, 2000 (02:33 PM PST Sunday, Feb 06, 2000).
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 2000 FEB 4 0139 31.72 36 2.23 120 35.92 0.72 27 .08 .2 .8 SLA 2.1D 85 4 NN 2000 FEB 4 1335 55.00 35 8.97 120 52.85 0.71 42 .15 .5 1.9 SSM # 2.4D 183 12 NN 2000 FEB 5 1256 11.58 38 44.37 122 55.13 6.16 30 .07 .2 .5 ROG 2.2D 44 7 WW 2000 FEB 5 1332 51.66 40 21.97 124 14.41 28.58 12 .08 .9 1.2 MEN 2.8D 184 12 WW 2000 FEB 5 2124 29.74 38 49.38 122 48.39 4.79 20 .05 .2 .6 GEY 2.0D 42 7 WW 2000 FEB 6 0529 22.66 38 46.51 122 45.13 2.91 8 .04 .9 1.7 GEY 2.0D 169 3 WW 2000 FEB 6 0543 24.22 38 45.28 122 55.21 3.01 35 .17 .2 1.6 ROG 2.3D 38 7 WW 2000 FEB 6 0854 59.20 39 1.72 122 35.42 0.08 20 .20 .4 3.1 BAR # 2.3D 94 9 WW 2000 FEB 6 2104 0.02 38 47.11 122 46.15 2.15 14 .04 .2 .5 GEY 2.0D 75 3 WW 2000 FEB 6 2233 37.63 37 32.60 118 49.93 0.95 16 .05 .3 .4 MOR 2.0D 165 5 WW 2000 FEB 8 1802 52.79 37 33.06 118 25.39 13.49 30 .06 .4 .8 CHV 2.3D 92 2 WW 2000 FEB 8 2358 30.54 35 25.78 120 42.94 5.97 34 .07 .2 .5 SSM 2.4D 68 4 WW 2000 FEB 9 0459 25.38 38 46.96 122 42.99 2.79 29 .08 .2 .4 GEY 2.4D 44 1 WW 2000 FEB 9 1556 4.19 38 48.53 122 50.54 2.78 25 .04 .2 .5 GEY 2.1D 37 4 WW
