Madison Myers – Assistant Professor at the Department of Earth Sciences, Montana State University
Title: Inferring magma ascent timescales and reconstructing conduit processes in rhyolitic explosive eruptions
Abstract: The mechanisms and timescales associated with the triggering of caldera-forming eruptions remain ambiguous and poorly constrained. Specifically, we lack methods for assessing the processes that initially drive magma from their long-term storage region into the conduit(s), and what controls the residence time of magma ascending through the conduit system(s). To access these rates, diffusion-based volatile methods are applied to quartz grains taken from the initial fall stratigraphy from four caldera-forming eruptions that show field evidence for contrasting opening behavior: (1) the Bishop Tuff, Long Valley (650 km3, 0.77 Ma), (2) the Oruanui eruption, Taupo NZ (530 km3, 25.4 ka), (3) the Huckleberry Ridge Tuff (2,500 km3, 2.1 Ma), (4) Bronze-Age eruption of Santorini volcano (30-60 km3, 3.6 ka).
Where: RUCH 103
When: Monday, November 4th