CAREER: Numerical Modeling of Volcanic Flank Instability Processes

Massive collapse of volcanic flanks is among the largest mass-wasting events on the planet and can evolve into energetic lateral blasts and spawn dangerous and destructive tsunami waves. Despite this hazard, the processes leading or aggravating the risk of flank collapse remain poorly understood. All volcanoes behave differently and the reasons behind initiation and persistence or arrest of flank collapse need to be explored and modeled accurately for a wide range of volcanoes affected by distinct flank processes. An initial suite of type-volcanoes comprises Kilauea (Hawaii), Piton de la Fournaise (France) and Anak Krakatau (Indonesia) for which extensive observations are available and where contrasting modes of recent failures are evident. This project will support an early-career, female assistant professor and her diverse research group to develop a suite of CAREER research and educational tools for investigating natural hazards and volcano processes. The project will fund two graduate students at Penn State, including a female international student, who will be educated in data processing, analysis, interpretation and process-based modeling. The research will be integrated in educational modules to develop FE models representing compelling examples of volcanic collapse and seismic unrest through engaging case studies. Undergraduate students will participate through senior theses with UNAVCO RESESS underrepresented interns additionally hosted at Penn State. The ensemble goal is to generate educational resources and teaching materials for courses in natural hazards, volcanology, and fault mechanics, including a large-enrollment General Education class for non-science majors. The work will exhance existing collaborations at Penn State, USGS, South Dakota School of Mines, Université de Savoie, and Piton de la Fournaise Observatory/IPGP France. Expected project outcomes have the potential to illuminate key mechanisms triggering and sustaining the massive collapse of volcano flanks and their associated and potentially catastrophic air- and sea-borne hazards.

This CAREER proposal addresses why the style, behavior, and timing of the cyclic growth then destruction of volcanic edifices varies across such a wide spectrum? It focuses on flank collapse on ocean island volcanoes and in using modeling to unravel the observed complexity in data sets representing a spectrum of type volcanoes. Specifically, this work will explore how styles of collapse are primarily controlled by the evolved size, steepness, structure, and strength of the edifice, in turn conditioned by rates of magma supply and composition and modulated by the aspect and slip interface properties of the substrate. Of key interest is how combinations of these characteristics define the unique signature of the anticipated collapse. Finite Element (FE) models will reproduce the spectrum of observed behaviors at ocean island volcanoes, defining key controls. An integrated study of geophysical observations will constrain process-based models of volcanoes affected by flank instability. To develop an understanding of how growth and collapse of ocean island volcanoes vary in style and timing, the researcher will benchmark and apply novel numerical modeling strategies using FE models for flank motion, with a focus on a complementary spectrum of volcano genetic types, sizes, and flank instability behaviors. An initial suite of type-volcanoes comprises Kilauea (Hawaii), Piton de la Fournaise (France) and Anak Krakatau (Indonesia) spanning large-to-small, shallow-to-steep and shield- to strato-volcano. A new numerical modeling strategy will be developed and benchmarked through synthetic tests, then applied to recent episodes of flank failure for a spectrum of volcanoes. The approach is interdisciplinary, relying on cutting-edge FE numerical modeling approaches to model deformation and failure and constrained by seismic and geodetic (ground-based and InSAR) data spanning multiple spatial and temporal scales. Mechanical properties of flank materials and the role of heterogeneities will be addressed using geophysical and geological observations, enabling key transient events promoting progress to collapse to be projected and defined.

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.