Ba, Sr, and Rb feldspar/melt partitioning in recent eruptions from Teide-Pico Viejo volcanic complex, Tenerife: New insights into pre-eruptive processes

The behaviour of Group I and II elements during the petrogenesis felsic igneous rocks is largely controlled by feldspar-liquid relationships. Numerous experimental studies have addressed plagioclase/melt element partitioning, with fewer devoted to potassium feldspar, very few albite-rich ternary-composition feldspar (An ∼ Or < Ab). However, partition coefficient for Ba known increase at least an order magnitude through crystallisation sequence sodic plagioclase–anorthoclase–potassium that typical alkaline suites. Feldspars, glasses, whole in such suites may exhibit strong enrichments depletions can be used track processes crystal fractionation, cumulate formation, recycling. Here, we review feldspar/melt partitioning data Ba, Sr, Rb all feldspars. Regression available provides expressions appear adequately model compositional temperature dependence coefficients compositions. We applied this melt compositions products several Holocene eruptions (Pico Viejo C, Pico H, Teide J2, Lavas Negras, Arenas Blancas, Montaña Rajada Reventada) basanitic-phonolitic suite Teide-Pico volcanic system (Tenerife, Spain), using EPMA LA-ICP-MS analyses. Comparing analysed feldspar/groundmass pairs predicted obtained models a way distinguishing between feldspars are or out equilibrium their host melt, reconstructing histories. results demonstrate existence distinct population had undergone accumulation, fusion recrystallisation events, Negras Blancas flows. In addition, anomalous trachytic composition Reventada due melting feldspar-dominated cumulate. Application these techniques active magmatic systems will allow us better understanding different pre-eruptive processes, ultimately improve hazard assessment.