Hi Bob,

Welcome to Earthwaves! Regarding the Old Faithful Geyser of California in Calistoga as Olga Kolbek, owner and retired junior high school teacher put it to me is not a natural geyser, but one which is piped in. It acts in a similar manners as most geysers. In 1972 she began keeping logs of its daily activities and began to notice changes before moderate to large earthquakes up to 200 miles away. In 1997 Dr. Paul Silver of Carnegie Institute took the records she gave him and computerized them and installed a 24/7 monitoring system on the property. As far as I know he has not papered the results of this experiment.

Olga is very senior in years now and no longer visits the geyser. In the spring of 2000 I interviewed her accompanied by my friend Elaine and family who are also avidly interested in earthquakes. She had a very interesting life and from meeting one of her classmates who I used to work with, I learned she was very much into holistic treatments long before it was an accepted norm. One of her home remedies for stomach upset for instance is to drink two tablespoons of flat coke. From what I've heard, it works quite well.

I do believe the geyser has been a good natural precursor to earthquakes, though I have not cataloged all of the moderate quakes and checked them against her records. I think for the handful that have obvious correlations, they are sufficient for me. Some include the 1984 Morgan Hill quake, the 5.9 Oroville quake and the 1989 Loma Prieta quake where the geysers schedule was changed dramatically 3 days prior to the earthquake.

Petra

• The Seismic Safety Zone