When: 3 p.m. Thursday, Nov. 29
Where: Micron Engineering Center, Room 106
Who: Philipp Ruprecht, research assistant professor at Lamont Doherty Earth Observatory in New York
Title: “The Highway from Hell: Mafic recharge and its role in volcanic eruptions at stratovolcanoes”
Abstract: Volcanic eruptions are among the most fascinating and destructive natural phenomena on Earth. They are ultimately fed and triggered by magmas generated in the mantle.
However, the role that mafic magmas play in modulating the eruptive behavior and how they transit the crust is typically obscured by cooling, crystallization, and magma mixing within a polybaric system of magma storage regions in the crust. Crystals growing before and during the magma processing in the crust are the recorders of the “evolving climate” in the magma plumbing system. Thus, magmatic crystals may retain information prior to hybridization and provide a direct view into the deeper parts of complex arc plumbing systems. In particular, the most primitive components (e.g., magnesian olivines) in an erupting magma shed light on the connection between primitive mantle-derived magmas recharging magmas residing in the crust and triggering their eruption. Zoning and elemental diffusion modeling in such olivines suggests that magma ascent from the magma source region in the mantle to the surface may be rapid (on the order of months to a year); despite transiting through mature arc crust that comprises long-lived low-density magma storage regions. While signs of volcanic unrest are typically monitored at the surface or upper crust, results suggesting rapid ascent from the mantle to the surface highlight that new monitoring efforts should set sights deeper, tracking magma movement from the base of the crust to the surface in the months to year run-up before eruptions.