Preliminary radon measurements at Villarrica volcano, Chile

We report data from a radon survey conducted at Villarrica volcano. Measurements have been obtained at selected sites by E-PERM (R) electrets and two automatic stations utilizing DOSEman detectors (SARAD Gmbh). Mean values for Villarrica are 1600 (+/- 1150) Bq/m(3) are similar to values recorded at Cerro Negro and Arena! in Central America. Moderately higher emissions, at measurement sites, were recorded on the NNW sector of the volcano and the summit, ranging from 1800 to 2400 Bq/m(3). These measurements indicate that this area could potentially be a zone of flank weakness. In addition, the highest radon activities, up to 4600 Bq/m(3), were measured at a station located near the intersection of the Liquine-Ofqui Fault Zone with the Gastre Fault Zone. To date, the Villarrica radon measurements reported here are, together with those collected at Galeras (Colombia), the sole radon data reported from South American volcanoes. This research may contribute to improving future geochemical monitoring and volcano surveillance. (C) 2013 Elsevier Ltd. All rights reserved.