The hydrogeochemistry of thermal springs on Mutnovskii Volcano, southern Kamchatka

This paper reports results from a hydrogeochemical study of thermal springs on Mutnovskii Volcano. The solutions of boiling pots and the pore water of thermal localities in the Donnoe Field were found to have an anomalous composition over a wide range of chemical elements, including rare earth elements (REE) and platinum-group elements (PGEs). The solutions of different springs exhibit considerable variations in their major and minor element compositions, indicating differences in the generation and upward transport of solutions. Physicochemical modeling showed that the mud pots studied could have been formed when the separate was ascending along an open fissure channel from the secondary zone of mixed boiling fluids. The high concentrations of titanium, vanadium, chromium, nickel, cobalt, REEs, and PGMs suggest a deep-seated source for these. The chemical forms of the elements in the solutions (primarily free aquaions) and the acidic environment favor high mobility of these elements. Deposition and concentration of these elements under near-surface conditions is unlikely.