The Parkfield Earthquake Prediction Experiment
The Parkfield earthquake prediction experiment was the outcome of much work on the seismological data. It was Bakun and Lindh’s 1985 paper which, on the basis that the last so-called characteristic Parkfield earthquake had occurred in 1966, predicted that the next one would occur some time before 1993. The US government became involved and extensive research and monitoring was undertaken (USGS).
But despite the close attentions of a small army of seismologists, the earthquake of around M6.0 did not occur within the predicted timescale. It was not until 2004, over ten years after the latest forecast date and almost 40 years after the previous event, that Parkfield was again shaken by a significant earthquake of M6.0.
There was much debate among scientists as to whether this did in fact constitute the expected characteristic earthquake or whether its occurrence was mere coincidence. In some aspects the earthquake did behave as expected but in others it did not. Overall it has to be concluded that the Parkfield experiment was a failure – and, as one of its initiators (among others) was to conclude, it demonstrated that demonstrates that ‘reliable short-term earthquake prediction still is not achievable’ (Bakun et al, 2005).
Although the Parkfield experiment failed in its intention of accurately predicting the date and place of a significant earthquake, it was nevertheless not without its benefits. The 2004 earthquake was probably the most intensively monitored up to that date and, in the words of the USGS, ‘our understanding of the earthquake process has already been advanced through research results from Parkfield’. The Parkfield section of the San Andreas Fault continues to be the location for earthquake monitoring and study.
WH Bakun and AG Lindh. “The Parkfield, California, Earthquake Prediction Experiment.” Science. (1985)
WH Bakun et al. “Implications for prediction and hazard assessment from the 2004 Parkfield earthquake.” Nature. (2005)
Y Rong, DD Jackson and YY Kagan. “Seismic Gaps and Earthquakes.” Journal of Geophysics Research. (2003)
US Department of the Interior and US Geological Survey. This Dynamic Planet map, 1994
US Geological Survey. “California-Nevada fault map for Parkfield” on the USGS website, accessed 23 May 2011.
US Geological Survey. “The Parkfield, California, Earthquake Prediction Experiment” on the USGS website, accessed 23 May 2011.
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