GEOCHEMICAL INDICATORS OF VOLCANIC ACTIVITY OF VOLCÁN DE COLIMA IN SPRING WATER

Monitoring the chemical fluctuations of springs near a volcano can provide insight into volcanic processes and predict volcanic events. This study observes how volcanic activity is reflected in the geochemistry of four springs near Volcán de Colima, Mexico’s most active volcano. Volcán de Colima does not consistently exhibit notable precursors to volcanic events, for example seismicity, and a greater understanding of the interactions between aquifers and volcanic fluids can improve hazard prediction. Samples were collected from 2002-2014, during which the volcano underwent effusive episodes in 2001-3, 2004, 2005, 2007-11, and 2013-14 and series of large Vulcanian explosions in 2003, 2005, and 2013. In situ measurements of temperature, pH, Eh, conductivity, and total dissolved solids were collected on a monthly basis, and the chemical compositions of the samples were analyzed for major ions. This data was then compared with volcanic activity, the level of which was defined by dates of major volcanic events and quantified by seismic activity levels and maximum explosion temperatures. The most significant correlation was that levels of boron sharply increased before effusive events. Simultaneous fluctuations of Cl/Mg ratio in all four springs may reflect increased contribution by volcanic fluids. Continued geochemical monitoring may be a valuable tool to predict or confirm potentially hazardous activity in Volcán de Colima.