Radon concentrations in thermal waters related to seismic events along faults in the Denizli Basin, Western Turkey

The aim of this study is to investigate the relationship between the earthquakes and radon concentrations in thermal waters along faults in the Denizli Basin, an area in Turkey known for its high seismic activity and thermal waters. This area was chosen because it exhibits active crustal movements combined with seismicity and there are numerous outflow thermal waters and gas outputs. In addition, this region has the type of tectonic activity where graben groups and faults take place.Measurements of radon levels and of some chemical and physical characteristics of thermal waters were made at seven sampling stations in the region.Radon concentrations were measured by a ZnS(Ag) scintillation counter in a collector chamber. The activity levels varied between 0.67 and 25.90kBqm-3 during the period of May–December 2000. In the evaluation of the results, the seismic data reported by Bogaziçi University Kandilli Observatory and Earthquake Research Institute, Seismological Laboratory were used. The increases observed in radon concentration at two stations were probably related to the earthquakes that took place in the region during the study period.