An earthquake of Mb 4.5 occurred west of Petrolia off the Coast
of Northern California this morning. The parameters (NEIS) of this
event are presently given as:

01/09/20 01:02:23 (PST) 40.44N 125.27W 2.4 MB=4.5 OFF COAST OF N CALIFORNIA

Don had a prediction for the area of Petrolia at this time (post # 9440
posted 9-13-01) which is attached below. The prediction was:

14-19 SEPT 40 km of 40.2 N 127.0 W M 3.4-5.6 240 km west of Petrolia

(Petrolia is located at 42.2N 124.2W).

Today's event occurred about 1 hour outside Don's time window, the magnitude
was in the middle of the given magnitude range and the location was
about 80 km west of Petrolia, about 140 km east of the expected epicenter.

Since June, 2000, there have been 6 events of Mb>=3.4 in the area
including both the predicted epicenter and the actual location (40-41N,
127-125W). The last event which was larger occurred on April 20, 2001
(Mb 4.8), five months ago. Since June 1, 2000 there have been 80
6-day windows, of which 6 contained an event of Mb>=3.4. The daily
probability of such an event is about 0.01, the probability of
randomly choosing a 6-day period which contained such an event is
about 0.075. Therefore the odds of success are about 1 in 13. Guessing,
Don would have been wrong 12 out of 13 times.

I should also mention that an event in the Ml 3.5 range did occur
on September 16 near Don's predicted epicenter (see post 9500 posted
on Sept 17 for details).

Because of the improbability of this event occurring within the time
frame Don had forecast and the closeness of the event to Don's
predicted parameters, I'll give Don a B+ on this prediction - not
perfect, but pretty darn close.

Don's forecast had been:

Petrolia, California Earthquake Forecast
Posted by Don In Hollister on September 13, 2001 at 15:16:28:

Magnitude: 3.4-5.6
From: 09/14/2001 - To: 09/19/2001
Location: Petrolia, California
Lat: 40.2N - Long: 127.0W - Range: 40Km

Hi All. This one has a fair chance of occurring on the specified date.

The magnitude should be in the range of 3.4Ml to 5.6Ml. The location will be
at 40.2N/127.0W. This is about 240Km west of Petrolia, California.

The most probable date is 09/16/2001. The window opens on 09/14/2001 and
closes on 09/19/2001. The radius on this will be 40Km.
Take Care...Don in creepy town

P.S. I see there was a small earthquake near Martinez this morning too.

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