Radon concentration anomalies as possible precursors to pyroclastic flow events of Arenal volcano

Abstract

Radon measurements were made at five stations located on Arenal volcano’s cone, Costa Rica, using LR-115 detectors. The radon measuring stations were located on the active cone and one station was located directly over a hotspring. Radon flux anomalies occurred just before the pyroclastic flow event of March 24, 25 and 26, 2001. The influence of external parameters over radon flux is neglected, because the most important atmospheric parameter is precipitation, that at the time of occurrence of the pyroclastic flow event was at its lowest level for the year.