Mercury Emissions Associated with Volcanoes and Geothermal Sources

There is some debate at present regarding the quantity of mercury naturally released by volcanoes and its relative significance to the natural Hg budget. In order to better understand the role of volcanoes in the global mercury budget a number of field campaigns were carried out to evaluate the Hg/S ratios in volcanic gases around the world. Measurements have been made of emissions of Masaya (Nicaragua), Etna and Vulcano (Italy), Tatun (Taiwan), Taal and Makiling (Philippines) and Kilauea (Hawaii, USA). Emissions from open vents, fumaroles, hot springs, bubbling mud pools and altered ground were investigated at these sites and concentrations of mercury elevated above background levels were …