So far they have not been able to determine the strength however I don't think it was that large, judging by the webicorder capture.
What is interesting though is that this indeed might be a fore-runner quake. Looking over these graphs, I find the motion of this quake interesting. It was also very shallow.
http://quake.wr.usgs.gov/waveforms/wavesshk/nc71362405.rsec0.html
here is the info still no determination on the strength.
Magnitude ? (uncertain or not yet determined)
Date-Time Friday, March 12, 2010 at 15:34:03 UTC
Friday, March 12, 2010 at 07:34:03 AM at epicenter
Location 40.741°N, 125.425°W
Depth 5 km (3.1 miles) (poorly constrained)
Region OFFSHORE NORTHERN CALIFORNIA
Distances 100 km (62 miles) W (281°) from Ferndale, CA
103 km (64 miles) W (271°) from Humboldt Hill, CA
105 km (65 miles) W (269°) from Bayview, CA
106 km (66 miles) W (267°) from Eureka, CA
417 km (259 miles) NW (307°) from Sacramento, CA
Location Uncertainty horizontal +/- 4.6 km (2.9 miles); depth +/- 15 km (9.3 miles)
Parameters Nph= 22, Dmin=109 km, Rmss=0.18 sec, Gp=274°,
M-type=”Nuttli” surface wave magnitude (mbLg), Version=0
Source California Integrated Seismic Net:
USGS Caltech CGS UCB UCSD UNR
Event ID nc71362405
I compared today’s still to be determined quake to last weeks 4.5. Note today’s though not as intense with the initial shock is much deeper with it rolling. This may be caused by it being a bit more shallow but I don’t think so.
Today’s(as posted above)
http://quake.wr.usgs.gov/waveforms/wavesshk/nc71362405.rsec0.html
Last Week’s 4.5
http://quake.wr.usgs.gov/waveforms/wavesshk/nc71359410.rsec0.html
You can compare the stations(most are on both)and see that to which I speak.
A few years ago, I recall looking at a series of quakes from . . . Long Valley etc. in California in an arc up through Nevada toward Yellowstone.
I think there was some argument about whether such could be related, or not.
Seemed obvious to me, an ignorant layman, given the timing, sequencing etc.
Do you know of any geologist connecting such things?