Reliable earthquake prediction is a worthwhile goal that, if ever attained, would reduce the loss of life and property.
Unfortunately, it is not at all clear that earthquake prediction is either possible or practical, and the entire subject remains controversial. Because this subject is of societal importance, the research staff of the USGS Geomagnetism Program has investigated published claims that geomagnetic and ionospheric signals associated with the earthquake process were measured prior to earthquake occurrence. So far, we have concluded that reported precursory signals are either bad data or the reported signals are part of normal global magnetic field variation that is unrelated to earthquakes.
Below are publications associated with this project.
Insignificant solar-terrestrial triggering of earthquakes
On the reported ionospheric precursor of the 1999 Hector Mine, California earthquake
On the reported magnetic precursor of the 1993 guam earthquake
On the reported magnetic precursor of the 1989 Loma Prieta earthquake
- Overview
Reliable earthquake prediction is a worthwhile goal that, if ever attained, would reduce the loss of life and property.
(Public domain.) Unfortunately, it is not at all clear that earthquake prediction is either possible or practical, and the entire subject remains controversial. Because this subject is of societal importance, the research staff of the USGS Geomagnetism Program has investigated published claims that geomagnetic and ionospheric signals associated with the earthquake process were measured prior to earthquake occurrence. So far, we have concluded that reported precursory signals are either bad data or the reported signals are part of normal global magnetic field variation that is unrelated to earthquakes.
- Publications
Below are publications associated with this project.
Insignificant solar-terrestrial triggering of earthquakes
We examine the claim that solar-terrestrial interaction, as measured by sunspots, solar wind velocity, and geomagnetic activity, might play a role in triggering earthquakes. We count the number of earthquakes having magnitudes that exceed chosen thresholds in calendar years, months, and days, and we order these counts by the corresponding rank of annual, monthly, and daily averages of the solar-teAuthorsJeffrey J. Love, Jeremy N. ThomasOn the reported ionospheric precursor of the 1999 Hector Mine, California earthquake
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 separateAuthorsJeremy N. Thomas, Jeffrey J. Love, Attila Komjathy, Olga P. Verkhoglyadova, Mark Butala, Nicholas RiveraOn the reported magnetic precursor of the 1993 guam earthquake
Using 1-second magnetometer data recorded 67 km from the epicenter of the 1993 Mw 7.7 Guam earthquake, Hayakawa et al. (1996) and Miyahara et al. (1999) identify anomalous precursory changes in ultra-low frequency magnetic polarization (the ratio of vertical to horizontal field components). In a check of their results, we compare their data (GAM) with 1-second data from the Kakioka observatory (KAAuthorsJ.N. Thomas, J.J. Love, M. J. S. Johnston, K. YumotoOn the reported magnetic precursor of the 1989 Loma Prieta earthquake
Among the most frequently cited reports in the science of earthquake prediction is that by Fraser-Smith et al. (1990) and Bernardi et al. (1991). They found anomalous enhancement of magnetic-field noise levels prior to the 18 October 1989 Loma Prieta earthquake in the ultra-low-frequency range (0.0110-10.001 Hz) from a ground-based sensor at Corralitos, CA, just 7 km from the earthquake epicenter.AuthorsJ.N. Thomas, J.J. Love, M. J. S. Johnston