Radon-222: A Potential Short-Term Earthquake Precursor

Abstract

This paper attempts to survey and catalog published short-term pre-earthquake precursors based on radon gas emissions. A series of papers were searched to collect relevant data, such as the epicentral distance, the extent, time and duration of the radon disturbance and to analyze the precursory value of each observable. In general, enhanced radon emissions have been observed prior to earthquakes and this has been recorded all over the world. The abnormal radon exhalation from the interior of earth has been associated with earthquakes and is considered an important field of research. The proposed physical models attempt to relate the observed radon disturbances with deformations occurring in the earth's crust prior to forthcoming earthquakes. While the models provide some physical explanations, there are many parameters that require further investigation.