It felt like a quick initial jolt followed up by three seconds of shaking to those of us in San Francisco. See what people thought about the latest rumblings of our San Andreas Fault over at SFist.com.
The updated report from the USGS indicates a 4.2 near the city of Milpitas.
Right here, “A” marks the spot:
A light earthquake occurred at 10:09:35 AM (PST) on Thursday, January 7, 2010.
The magnitude 4.2 event occurred 10 km (6 miles) ENE of Milpitas, CA.
The hypocentral depth is 9 km ( 6 miles).
|Magnitude||4.2 – local magnitude (ML)|
|Time||Thursday, January 7, 2010 at 10:09:35 AM (PST)
Thursday, January 7, 2010 at 18:09:35 (UTC)
|Distance from||Milpitas, CA – 10 km (6 miles) ENE (62 degrees)
Alum Rock, CA – 12 km (8 miles) NNE (12 degrees)
Sunol, CA – 16 km (10 miles) SSE (150 degrees)
San Jose City Hall, CA – 17 km (11 miles) NNE (29 degrees)
|Coordinates||37 deg. 28.6 min. N (37.477N), 121 deg. 47.8 min. W (121.797W)|
|Depth||9 km (5.6 miles)|
|Location Quality Parameters||Nst= 89, Nph= 89, Dmin=3 km, Rmss=0.08 sec, Erho=0.1 km, Erzz=0.4 km, Gp=36 degrees|
|Additional Information||map with fault names
Google Earth KML (Requires Google Earth.)
ShakeMap shaking intensity maps
NCSS First Motion Mechanism 1
As per usual, t’was the Northern Calaveras (it means “skulls”) branch of the San Andreas. Alum Rock, will you ever win?
Tags: (BART), 10:09, 10:10, 2010, 4.1, 4.2 magnitude, 7th, Alameda, alum rock, am, bay area, Bay Area Rapid Transit, branch, calaveras, california, Contra Costa, county, earthquake, Earthquake Hazards Program, january, light, magnitude, marin, milpitas, moderate, morning, Muni, resevoir, richter, richtor, san andreas, san francsico, san jose, San Mateo, Santa Clara, scale, sunol, TRACKS, transit, tunnel, U.S. Geological Survey, usgs