GTSM at Parkfield, California



Background to the Parkfield Experiment shown in the accompanying map.

The earthquake monitoring experiment at Parkfield began in earnest in 1985 after a forecast with a 95% confidence that a M6 earthquake would occur near Parkfield before 1993 near the site of the 1966 M6 earthquake.The primary goals for deploying instruments around Parkfield were to record geophysical signals that accompany the earthquake process, to measure ground motion in the near-field of the forecasted earthquake, and to issue a warning 3-days prior to the anticipated M6 event if seismicity and/or fault creep reach pre-defined threshold levels(Parkfield Working Group, 1987 and Michael and Jones, 1998).


The event did not happen till Sept 2004, by which time many of the original experiments were failing.      Many important results were obtained over the period from 1985 to 2005 solely because the region was being intensely monitored using a wide range of investigative methods.