Anomalous soil mercury concentrations at Paricutin Volcano, Michoacan - Guanajuato Volcanic Field. Mexico

Abstract

The identification of anomalous (>1 200 ppb) soil mercury (Hg) concentrations on the southwest flank of Paricutin volcano provides new insight into the nature of convective gas flux from magma beneath this quiescent cinder cone. Anomalous soil Hg concentrations are identified over an area of approximately 1 km², an area of upwelling that is much larger than is indicated by the distribution of high temperature (>1000C) fumaroles. Soil Hg samples with background (>199 ppb) Hg concentrations are mapped over an área of approximately 3 000 km², within the Michoacan - Guanajuato volcanic field. Background soil Hg concentrations in this volcanic field are comiderably greater than those reported from other survey areas, and often increase near cinder cone alignments. High background Hg concentrations in the field may be related to a high fault density.