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
Information about seismicity for other regions is available from the U.S. Geological Survey Earthquake Hazards Program Website. 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 provided at the Northern California Maps of Recent Earthquake Activity website. 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 minor earthquake of magnitude 3.9, 8 miles WNW of Toms Place, CA at 02:44 PM UTC Saturday, 06 28, 2008 (07:44 AM PDT Saturday, Jun 28, 2008).
The largest event to occur this week in this region was an earthquake of magnitude 2.0, 6 miles ESE of Napa, CA at 08:54 AM UTC Tuesday, 07 01, 2008 (01:54 AM PDT Tuesday, Jul 01, 2008).
The largest event to occur this week in this region was a minor earthquake of magnitude 3.9, 8 miles WNW of Toms Place, CA at 02:44 PM UTC Saturday, 06 28, 2008 (07:44 AM PDT Saturday, Jun 28, 2008).
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 2008 JUN 25 0411 44.34 36 34.85 121 10.54 6.70 70 .07 .1 .3 2.9L 36 1 2008 JUN 25 0420 4.94 36 34.89 121 10.65 6.35 72 .06 .1 .3 2.3D 38 1 2008 JUN 26 0526 51.38 37 31.91 118 48.97 7.32 44 .05 .2 .5 3.2L 58 7 2008 JUN 26 1713 55.21 38 48.01 122 44.38 2.36 61 .06 .1 .2 2.8D 51 2 2008 JUN 26 2030 6.12 38 47.23 122 45.14 2.97 51 .08 .1 .2 2.1D 40 1 2008 JUN 26 2316 41.47 40 8.01 122 8.55 30.05 28 .28 .6 .9 2.5D 54 8 2008 JUN 27 0047 34.82 38 48.84 122 46.90 1.81 31 .05 .2 .2 2.1D 49 0 2008 JUN 27 0141 7.30 40 37.17 121 48.13 17.74 20 .08 .4 .9 2.0D 57 13 2008 JUN 27 1253 4.77 37 26.23 118 33.69 17.21 42 .06 .2 .5 2.5D 41 7 2008 JUN 28 0305 42.33 36 26.08 121 1.79 0.26 27 .17 .4 .5 2.0D 103 1 2008 JUN 28 0406 24.23 36 26.01 121 1.59 0.41 15 .20 .6 .7 2.1D 113 1 2008 JUN 28 0554 54.30 35 59.86 120 33.96 3.78 54 .13 .2 .3 2.1D 81 3 2008 JUN 28 1444 10.51 37 35.09 118 49.13 11.92 45 .06 .2 .4 3.9W 51 1 2008 JUN 28 1609 22.30 37 23.90 118 46.16 13.06 41 .05 .3 .6 2.7D 126 8 2008 JUN 28 1711 48.18 41 52.44 121 57.71 11.53 14 .26 1.0 5.7 2.0D 177 44 2008 JUN 28 2310 12.20 37 35.57 118 48.92 12.91 43 .05 .2 .4 2.4D 79 1 2008 JUN 28 2355 59.66 36 23.68 120 38.20 10.08 49 .09 .1 .3 2.1D 57 17 2008 JUN 29 0041 41.77 36 33.55 121 4.26 7.07 49 .10 .1 .3 2.1D 46 4 2008 JUN 29 0601 27.59 39 24.93 123 17.29 4.51 33 .09 .2 .6 2.4D 55 19 2008 JUN 29 1606 27.25 38 49.50 122 47.73 3.64 69 .07 .1 .2 2.7D 23 1 2008 JUN 30 0533 43.61 37 37.37 119 3.01 4.23 36 .08 .2 .3 2.1D 65 2 2008 JUN 30 0533 47.19 37 37.59 119 2.39 2.79 8 .03 .531.6 2.0D 99 4 2008 JUN 30 0544 31.84 37 37.35 119 2.90 4.18 44 .07 .2 .2 2.0D 68 2 2008 JUN 30 1620 57.39 38 49.31 122 47.75 3.75 44 .06 .2 .3 2.1D 34 1 2008 JUN 30 2240 37.15 39 35.00 123 22.60 8.00 17 .05 .231.6 2.5D 85 7 2008 JUL 1 0310 20.40 39 20.94 123 16.91 5.32 21 .04 .2 1.3 2.3D 43 16 2008 JUL 1 0606 11.24 38 46.13 122 43.18 1.67 34 .05 .1 .2 2.1D 48 2 2008 JUL 1 0854 29.91 38 15.84 122 10.85 9.02 41 .17 .3 1.0 2.0D 101 4 2008 JUL 1 1820 43.93 38 48.45 122 48.84 3.46 50 .07 .2 .2 2.1D 33 1 2008 JUL 1 1841 58.42 37 28.61 118 50.59 8.74 36 .05 .3 .8 2.0D 119 11