Hi All. Just thought I would put my 2 bits worth in here. Take Care…Don in creepy town

“Earthquake prediction is a popular pastime for psychics and pseudo-scientists, and extravagant claims of past success are common. Predictions claimed as "successes" may rely on a restatement of well-understood long-term geologic earthquake hazards, or be so broad and vague that they are fulfilled by typical background seismic activity. Neither tidal forces nor unusual animal behavior have been useful for predicting earthquakes. If an unscientific prediction is made, scientists can not state that the predicted earthquake will not occur, because an event could possibly occur by chance on the predicted date, though there is no reason to think that the predicted date is more likely than any other day. Scientific earthquake predictions should state where, when, how big, and how probable the predicted event is, and why the prediction is made. The National Earthquake Prediction Evaluation Council reviews such predictions, but no generally useful method of predicting earthquakes has yet been found.”

“One well-known successful earthquake prediction was for the Haicheng, China earthquake of 1975, when an evacuation warning was issued the day before a M 7.3 earthquake. In the preceding months changes in land elevation and in ground water levels, widespread reports of peculiar animal behavior, and many foreshocks had led to a lower-level warning. An increase in foreshock activity triggered the evacuation warning. Unfortunately, most earthquakes do not have such obvious precursors. In spite of their success in 1975, there was no warning of the 1976 Tangshan earthquake, magnitude 7.6, which caused an estimated 250,000 fatalities.”

“According to a recent review of the Parkfield experiment by a working group (B. Hager, Chair) of the National Earthquake Prediction Evaluation Council [1993], the experiment has brought scientists together with state and local officials, emergency managers, and the news media, in a productive, mutually beneficial relationship. The State established the first scientifically based State emergency management protocol for a specific predicted earthquake. The first A-level alert was issued on Oct. 22, 1992. The USGS notified the California Office of Emergency Services (OES) of an A-level alert triggered by the M=4.7 earthquake at Middle Mountain. Eight minutes later, OES broadcast the alert to State agencies and local governments over the California Warning System. Kern County was the first county to activate its Emergency Operation Center, 47 minutes after the OES alert. OES completed its alert of local government and response officials in less than one hour following the earthquake. It was a complete success on the part of transmitting earth science information to the public.” The assessment represented a major change from Sunday, when -- after a swarm of 25 temblors -- the strongest a moderate magnitude 4.8 -- federal and state authorities declared their highest-level earthquake alert in a seven-county region surrounding the Central California town of Parkfield. Scientists said the odds of a strong earthquake within a 72-hour period were one-in-three.

Geological Survey spokeswoman Pat Jorgenson said instrument recordings along the San Andreas fault segment near Parkfield, 180 miles northwest of Los Angeles, showed very little seismic activity as Monday wore on.

Other instruments in the vicinity -- measuring any creep of the sides of the fault, subterranean strain and water well levels -- also showed normal readings. Jorgenson said the chances of a sizable earthquake would be elevated if anomalies in these categories were to show up, even without an increase in small quakes.

The "A"-level alert issued Sunday in the seven counties -- Monterey, Fresno, San Benito, Kings, Kern, San Luis Obispo and Santa Barbara -- marked only the second time that the Geological Survey and the California Office of Emergency Services have issued the high-grade warning in an earthquake forecasting experiment begun in 1985.

There were two warnings issued for the Loma Prieta quake. One was 15 months prior to the quake the other was 2 months prior to the quake. Both alerts were based on two M>5.0+ quakes. Each alert was 5 days long. It is now known that although these two quakes didn’t trigger the Loma Prieta they did create a little room for the fault to move which in turn caused the Loma Prieta quake.

Reference:

http://www.agu.org/revgeophys/aki00/node3.html

http://216.239.57.104/search?q=cache:x3tRtLrolB8J:www.geophys.washington.edu/SEIS/PNSN/INFO_GENERAL/eq_prediction.html+National+Earthquake+Prediction+Evaluation+Council+&hl=en&ie=UTF-8