U-series histories of magmatic volatile phase and enclave development at Soufrière Hills Volcano, Montserrat

Abstract Injection of volatile-rich mafic magma prior to an eruption may trigger episodes volcanism and can act transfer metals from depth. However, petrologic knowledge the timescales injection have thus far been focussed on mineral-scale studies chemical zoning patterns. The study enclaves dispersed within products provide insights into interaction between deep shallow reservoirs. We combine 238U-230Th-226Ra-210Pb isotope data with trace element concentrations across interface two contrasting in contact their host andesite 2010 at Soufriere Hills Volcano (SHV), Montserrat investigate history mass exchange enclave host. application these time-sensitive isotopes highlights complexities volatiles metal elements magmas enclaves' potential as triggers. exhibit (210Pb/226Ra)0 ratios >1 consistent volatile input subsurface plumbing system a few decades eruption. Samples andesitic host, however, which make up bulk eruptive products, (210Pb/226Ra)0 ≤ 1 suggesting no net gain leading eruption, or that melt-volatile is timescale unresolvable by 210Pb 226Ra systematics (i.e.