Jim Berkland County Geologist for Santa Clara County from 1973 until he retired in 1994. Berkland's predictions have been either self-published in his newsleter or website, or announced in various interviews or speaking engagements. His notoriety arose from an interview published in the Gilroy Dispatch on October 13, 1989, where he predicted that an earthquake with a magnitude between 3.5 and 6.0 would occur in the San Francisco Bay Area between October 14 and October 21. The 6.9-magnitude Loma Prieta earthquake occurred on October 17, just four days later. Berkland claims that government officials told him not to make any more predictions,
Earthquake prediction "resoundingly debunked". Probably the most celebrated seismo-electromagnetic event ever, and one of the most frequently cited examples of a possible earthquake precursor, is the 1989 Corralitos anomaly. In the month prior to the 1989 Loma Prieta earthquake measurements of the earth's magnetic field at ultra-low frequencies by a magnetometer in Corralitos, California, just 7 km from the epicenter of the impending earthquake, started showing anomalous increases in amplitude. Just three hours before the quake the measurements soared to about thirty times greater than normal, with amplitudes tapering off after the quake. Such amplitudes had not been seen in two years