Volcanoes for Cryosphere and Atmosphere (VolCA) - Volcano plumbing systems and eruptions in northern Victoria Land: implications for ice cover and atmospheric circulation.

Our Planet Earth is made of interlinked geological systems. Volcanic activity connects the deep Earth interior with the external envelopes such as atmosphere, hydrosphere and, at high latitudes, cryosphere. Therefore, the products of Antarctic volcanoes, active since the Miocene, represent terrestrial and marine records of the history of their paths through the ice and the air. This project is designed to study (A) glaciovolcanic products, (B) subvolcanic plumbing systems and (C) deposits of explosive volcanic eruptions (tephra) with the aim of extracting from them paleoenvironmental information. (A) The cryospheric load act as a modulator of volcanic eruptions and, possibly, also of magma production in the mantle. The timing of volcanic eruptions in glaciated terrains is potentially modulated by climate-controlled variations in the glacio-lithostatic load, that is the pressure acting on underlying volcanic plumbing systems. The structure and activities of volcano plumbing systems will be investigated and eruptions dated isotopically. Correlations will be attempted between glacial cycles and magma eruptibility. (B) Volcanic morphologies and lithofacies of the volcanic products in glaciated terrains are generated under the controlling influence of ice thickness and type. Critical insights on these parameters can be extracted from field observations of morphologies and lithofacies and reconstruction of eruption pressure. A chronological framework of the ice thickness will be defined by means of isotopic dating. (C) The fragmental products of explosive volcanic eruptions (tephra) can travel both locally and at a continental scale -and beyond- and are distributed according to the atmospheric currents. The vast collection of tephra from ice and marine sediments is offering samples to be fingerprinted and correlated to specific eruptions of Antarctic volcanoes, giving insights into atmospheric circulation in Antarctica at the time of the isotopically dated eruption.