Springwater Chemical Anomalies Prior To the Mw = 7.2 Van Earthquake (Turkey)

Abstract

We performed chemical analyses of commercially bottled spring water (EREK Spring water) emanating from a location less than 20 kilometer from the epicenter of the Mw = 7.2 Van Earthquake of October 23rd 2011. The available water samples cover the period from September 8th 2011 to January 11th 2012. The pre-earthquake anomaly is characterized by a slight but clear increase in Ca2+, Mg2+, K+ and Cl- contents and decrease in Na+ and SO42- contents compared to the background. Post-seismic samples show decreasing trends in Ca2+, Mg2+, K+ and Cl- and increasing trends in Na+ and SO42-. All ion concentrations reach stability approximately one month after the earthquake. These results indicate that spring water chemical anomalies may be monitored as potential geochemical pre-earthquake indicators. © 2012, GEOCHEMICAL SOCIETY OF JAPAN. All rights reserved.