CAREER: Long-term Controls on Short-term Patterns of Magmatism: Towards a Unified Framework for Crustal Magma Transport

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Determining the pathways and timing of magma migration between the source region and Earth's surface remains one of the biggest challenges for understanding volcanic eruptions and their hazards. Predicting volcanic activity must contend with magma transport processes that are hidden beneath the surface and that reflect an integrated history of magmatic and tectonic events spanning far beyond direct observational records. Magmatism of any kind associated with the largest volcanic eruptions in the geologic record has never been directly observed, which complicates efforts to understand how volcanoes active today fit into the spectrum of possible volcanic processes. This proposal will generate new understandings of magma transport on scales that are relevant both to predicting active volcanic processes and to interpreting the record of past eruptions. Broader impacts associated with this proposal will leverage the great diversity of volcanic data to develop sonification and visualization software tools for use in teaching, outreach, and as a bridge to the arts. Undergraduate teaching and workshops will generate geoscience education materials. A series of outreach presentations will use sonification and visualization techniques to bring project research to the public, including a collaboration with musicians to produce recordings and performances of sonified volcanic data. There are two primary scientific objectives of this proposal. The first objective is to understand the spatiotemporal progression of magmatism at its largest scales, focusing on the iconic Columbia River Flood Basalts. New field data describing a massive exposed feeder dike system in eastern Oregon, USA, will be combined with thermochronology and related techniques that constrain timescales of subsurface magma flow. Numerical models will elucidate physical processes controlling the tempo, volumes, and crustal transport architecture feeding flood basalt eruptions, using Bayesian inversion methods to formally assess model uncertainty amongst diverse but indirect observational constraints. This work should provide a predictive basis for connecting flood basalt eruptions to environmental impacts including climate and mass extinctions of life. The second objective is to develop a modeling framework for crustal magma transport that captures multiphase fluid movement and surface eruption cycles through a network of reservoirs and conduits, coupled to a crustal model that accounts for the thermomechanical history of prior magmatism, far-field forcing (i.e. from tectonics, climate), and nonlinear rheology of crustal materials. This modeling framework will be used to explore the phenomenological trade-offs in physical and chemical processes that govern eruption cycles, and explore the complexities of history-dependent crustal stress and thermal evolution at long-lived magmatic centers. Applications to historical volcanic datasets as well as the Columbia River Flood Basalts will provide an observational test for models, while comparison to and calibration with fully phase-resolved simulations performed by others will help bridge divergent approaches to modeling multi-scale magma transport.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.