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On the reported ionospheric precursor of the 1999 Hector Mine, California earthquake

March 24, 2012

Using Global Positioning System (GPS) data from sites near the 16 Oct. 1999 Hector Mine, California earthquake, Pulinets et al. (2007) identified anomalous changes in the ionospheric total electron content (TEC) starting one week prior to the earthquake. Pulinets (2007) suggested that precursory phenomena of this type could be useful for predicting earthquakes. On the other hand, and in a separate analysis, Afraimovich et al. (2004) concluded that TEC variations near the epicenter were controlled by solar and geomagnetic activity that were unrelated to the earthquake. In an investigation of these very different results, we examine TEC time series of long duration from GPS stations near and far from the epicenter of the Hector Mine earthquake, and long before and long after the earthquake. While we can reproduce the essential time series results of Pulinets et al., we find that the signal they identify as anomalous is not actually anomalous. Instead, it is just part of normal global-scale TEC variation. We conclude that the TEC anomaly reported by Pulinets et al. is unrelated to the Hector Mine earthquake.

Publication Year 2012
Title On the reported ionospheric precursor of the 1999 Hector Mine, California earthquake
DOI 10.1029/2012GL051022
Authors Jeremy N. Thomas, Jeffrey J. Love, Attila Komjathy, Olga P. Verkhoglyadova, Mark Butala, Nicholas Rivera
Publication Type Article
Publication Subtype Journal Article
Series Title Geophysical Research Letters
Index ID 70156901
Record Source USGS Publications Warehouse
USGS Organization Geologic Hazards Science Center