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NORTHERN CALIFORNIA

Saturday, October 31, 2009 at 06:52:23 UTC

Preliminary Earthquake Report

Versión en Español

Magnitude
Date-Time	Saturday, October 31, 2009 at 06:52:23 (UTC) - Coordinated Universal Time Friday, October 30, 2009 at 11:52:23 PM local time at epicenter Time of Earthquake in other Time Zones
Location	38.79N 122.76W
Depth	5 kilometers
Region	NORTHERN CALIFORNIA
Distances	20 km (15 miles) SSW of Clearlake, California 40 km (25 miles) N of Santa Rosa, California 55 km (35 miles) SE of Ukiah, California 115 km (70 miles) WNW of SACRAMENTO, California
Location Uncertainty	Error estimate not available, held by USGS NEIC to another agency's solution
Parameters	not available
Source	Northern California Seismic Network, UC Berkeley & USGS Menlo Park, USA
Remarks	Felt (III) at Geyserville and (II) at Healdsburg, Middletown and Santa Rosa. Also felt at Angwin, Calistoga, Cupertino, Danville, Hidden Valley Lake, Kelseyville, Marysville, Napa, Sonoma and Windsor.
Event ID	usnkaj

Location Maps Did You Feel It? Report shaking and damage at your location. You can also view a map displaying accumulated data from your report and others. Historic Seismicity Theoretical P-Wave Travel Times Historic Moment Tensor Solutions Seismic Hazard Map Earthquake Density Maps USGS National Seismic Hazard Mapping Project Current information about the rate at which earthquakes occur in different areas, and on how far strong shaking extends from the earthquake source. Earthquake Information for California San Francisco Regional Earthquake Map Earthquakes: Frequently Asked Questions

NB: The official magnitude for this earthquake is indicated at the top of this page. This was the best available estimate of the earthquake's size, at the time that this page was created. Other magnitudes associated with web pages linked from here are those determined at various times following the earthquake with different types of seismic data. Although, given the data used, they are legitimate estimates of magnitude they are not considered the official magnitude.

The region name is an automatically generated name from the Flinn-Engdahl (F-E) seismic and geographical regionalization scheme. The boundaries of these regions are defined at one-degree intervals and therefore differ from irregular political boundaries. More->

Preliminary Earthquake Report
U.S. Geological Survey, National Earthquake Information Center
World Data Center for Seismology, Denver