Building damaged during the Loma Prieta earthquake

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, research staff of the USGS Geomagnetism Program have 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.

Example analyses of reported earthquake-prediction results published by USGS scientists include:

Primary USGS contact: Jeffrey J. Love