Dislocation model for radon response to distant earthquakes

Abstract

If radon changes associated with earthquakes are caused by changes in strain within the earth, reports of radon signals that are measured at considerable distances from the hypocenters of earthquakes can be understood. A simple dislocation model leads to estimates of distances that increase to hundreds of kilometers at earthquake magnitudes of 5 and above. The essential components of the theory are that the strain from a dislocation loop varies at large distances x as x −3 , while the strains increase with the magnitude of the earthquake represented. A threshold sensitivity is inferred from radon measurements associated with earthquakes near Blue Mountain Lake, New York. The usefulness of a global 222 Rn‐monitoring network is inferred.