Characterization of magmatic storage conditions following a mafic recharge event
Jakob Scheel1 ; Philipp Ruprecht1; Michael Gardner2
Affiliations: 1Department of Geological Sciences and Engineering, University of Nevada, Reno; 2Department of Civil and Environmental Engineering, University of California, Davis
Presentation type: Poster
Presentation time: Monday 16:30 - 18:30, Room Poster Hall
Poster Board Number: 67
Programme No: 1.2.12
Abstract
Understanding the long-term storage conditions of silicic magma in the Earth's crust is crucial for interpreting volcano monitoring data and predicting volcanic eruptions. Recently, the volcanology community has been interested in the timescales over which large volumes of detectable magma exist in the crust before eruption, and how magma mixing or mafic recharge may trigger volcanic activity. We study mafic enclaves, which link the mixing process and the archive for transient thermal conditions in a unique way as they are also inherently the agents of recharge. This study aims to assess how long magmatic systems reside in a state of elevated storage temperature following a magmatic recharge and what the temperatures involved during a recharge are. By answering these questions, we can on the one hand gain insights into the timescales of elemental diffusion, which constrains the rates of mixing and ascent before and during eruption. On the other hand, our results can provide constraints for dynamic models that explore mixing and hybridization through a first-order documentation of the temperature variance in a system. To capture the response of the system to the transient thermal signals on timescales of months to decades, we are applying a Magnesium-in-plagioclase thermometer and geospeedometer on mafic enclaves from the Chaos Crags (Lassen Volcanic National Park), that have clinopyroxene-plagioclase pairs preserved and thus allow us to ignore issues related to a moving boundary by acting as a diffusion-couple.