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 2.6 20 miles W of Eureka, CA at 10:37 AM UTC Tuesday, Nov 30, 1999 (02:37 AM PST Tuesday, Nov 30, 1999).
The largest event to occur this week in this region was a microearthquake of magnitude 2.4 1 miles SSE of Bolinas, CA at 01:51 PM UTC Monday, Nov 29, 1999 (05:51 AM PST Monday, Nov 29, 1999).
The largest event to occur this week in this region was a microearthquake of magnitude 2.2 8 miles SW of Toms Place, CA at 07:01 AM UTC Tuesday, Nov 30, 1999 (11:01 PM PST Monday, Nov 29, 1999).
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 N RMS ERH ERZ LOC PREF YR MON DA HRMN SEC DEG MIN DEG MIN KM RD S SEC KM KM REMKS MAG 99 NOV 25 354 7.62 38 49.31 122 47.64 4.39 28 .06 .2 .4 GEY 2.3D 99 NOV 25 2212 38.59 39 50.80 122 55.23 0.91 26 1 .16 .3 4.8 SAC # 2.2D 99 NOV 26 2110 11.00 41 5.98 123 38.60 25.18 18 1 .07 .2 .8 KLA 2.4D 99 NOV 27 1548 17.34 38 46.63 122 44.61 4.30 36 1 .05 .2 .3 GEY 2.3D 99 NOV 28 737 59.80 40 45.42 124 24.55 21.73 19 1 .04 .4 .6 EUR 2.1D 99 NOV 28 1002 24.99 36 47.25 118 13.31 9.62 31 .06 .5 1.2 OWV 2.3D 99 NOV 28 2037 4.39 38 48.10 122 45.13 1.88 25 .06 .1 .4 GEY 2.2D 99 NOV 28 2250 31.31 36 27.77 121 2.34 6.33 55 2 .06 .1 .3 BIT 2.6D 99 NOV 29 21 25.33 37 29.05 121 34.59 6.63 47 .07 .2 .5 HAM 2.3D 99 NOV 29 1351 9.31 37 53.68 122 40.34 7.56 41 1 .08 .2 .3 MAR 2.4D 99 NOV 30 701 39.59 37 28.04 118 46.11 15.41 29 .06 .4 .7 WCN 2.2D 99 NOV 30 953 58.95 38 40.50 122 54.38 4.84 34 .10 .1 .7 ROG 2.2D 99 NOV 30 1037 48.81 40 48.63 124 32.89 18.71 22 .09 .8 1.1 EUR 2.6D 99 NOV 30 1902 37.92 36 16.90 120 52.06 9.25 44 .14 .2 .5 BIT 2.5D 99 DEC 1 1723 48.94 37 56.02 122 17.29 8.84 41 .07 .1 .3 HAY 2.3D