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 light earthquake of magnitude 4.0, 3 miles SSE of Parkfield, CA at 11:34 AM UTC Tuesday, 05 22, 2007 (04:34 AM PDT Tuesday, May 22, 2007).
The largest event to occur this week in this region was a minor earthquake of magnitude 3.3, 9 miles E of San Jose City Hall, CA at 11:10 PM UTC Sunday, 05 20, 2007 (04:10 PM PDT Sunday, May 20, 2007).
The largest event to occur this week in this region was a microearthquake of magnitude 2.0, 7 miles W of Toms Place, CA at 08:43 AM UTC Saturday, 05 19, 2007 (01:43 AM PDT Saturday, May 19, 2007).
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 2007 MAY 17 0216 33.62 38 29.72 122 43.71 5.82 55 .10 .1 .3 3.0D 36 6 2007 MAY 17 1438 26.48 36 48.15 121 31.52 6.78 43 .07 .2 .4 2.1D 35 4 2007 MAY 17 1823 12.39 38 49.14 122 47.90 3.77 24 .06 .2 .7 2.6D 53 1 2007 MAY 17 2342 23.44 39 28.10 123 4.91 4.87 31 .04 .1 .6 2.0D 40 13 2007 MAY 18 0019 19.18 35 48.34 121 21.69 4.63 57 .06 .2 .2 2.3D 179 10 2007 MAY 18 0527 14.13 36 40.52 121 18.15 6.23 54 .04 .1 .3 2.4D 40 3 2007 MAY 18 0838 40.28 38 48.29 122 48.94 4.75 31 .04 .2 .4 2.5D 40 2 2007 MAY 18 0855 48.57 36 33.97 121 9.41 2.90 59 .06 .1 .3 2.9D 38 3 2007 MAY 19 0502 8.52 38 49.16 122 48.08 3.20 41 .04 .1 .4 2.2D 36 1 2007 MAY 19 0843 44.10 37 34.14 118 48.39 6.62 41 .05 .2 .4 2.0D 84 3 2007 MAY 19 1153 59.35 38 49.88 122 52.19 3.03 33 .06 .2 .8 2.3D 34 7 2007 MAY 19 1545 44.13 39 28.09 123 4.98 4.44 33 .06 .1 .8 2.3D 29 13 2007 MAY 19 1849 21.05 40 17.28 124 25.17 21.70 25 .10 .9 .2 2.6D 228 10 2007 MAY 20 0813 13.45 40 18.39 122 12.35 24.22 23 .14 .3 .9 2.8D 37 13 2007 MAY 20 1042 42.70 37 24.83 121 45.70 7.68 92 .08 .1 .4 2.1D 40 5 2007 MAY 20 1142 15.49 38 49.22 122 48.18 0.04 39 .37 .4 2.1 2.7D 36 2 2007 MAY 20 2310 19.54 37 21.84 121 43.62 6.77107 .09 .1 .2 3.3L 35 4 2007 MAY 22 0351 11.45 38 49.35 122 47.98 4.28 35 .06 .1 .3 2.1D 37 2 2007 MAY 22 0902 2.50 39 2.58 123 7.42 4.87 25 .05 .2 .6 2.1D 63 7 2007 MAY 22 0944 18.71 38 48.64 122 47.58 4.01 35 .07 .1 .4 2.5D 38 0 2007 MAY 22 1134 12.15 35 51.68 120 24.73 9.19 77 .07 .1 .2 4.0W 42 2 2007 MAY 22 1850 41.90 37 33.09 118 48.61 14.02 45 .07 .2 .5 2.0D 88 5
