Thermal-Hydrologic Mechanism for Rainfall-Triggered Collapse of Lava Domes

Authors

D. Elsworth, Pennsylvania State University
B. Voight, Pennsylvania State University
Glenn Thompson, British Geological SurveyFollow
S. R. Young, Pennsylvania State University

Document Type

Article

Publication Date

2004

Keywords

lava dome, rainfall, instability, pyroclastic flows, hazard

Digital Object Identifier (DOI)

https://doi.org/10.1130/G20730.1

Abstract

Hazardous gravitational collapses involving hot lava domes can be triggered by intense rainfall, both in periods of active dome growth and volcanic repose. The collapses can evolve into energetic failures involving as much as 90% of the dome, or >100 × 10⁶ m³ of dome lava, retrogressively removed over several hours. Understanding such potentially lethal phenomena is vital, but traditional explanations for rain-induced slope failure are problematic for rainfall on hot (typically >400 °C) crystalline lava. In this paper we quantitatively develop a new thermal-hydrologic mechanism that can cause such failures: pressure buildup within fissures due to effusive gas trapped by a rain-saturated dome carapace results in increased destabilizing forces and the loss of mass strength, and ultimately results in failure of the dome. Our mechanistic models are consistent with field observations and provide a quantification of threshold rainfall intensities and durations required to trigger failure.

Rights Information

Terms of use for work posted in Scholar Commons.

Was this content written or created while at USF?

No

Citation / Publisher Attribution

Geology, v. 32, issues 11, p. 969-972

Scholar Commons Citation

Elsworth, D.; Voight, B.; Thompson, Glenn; and Young, S. R., "Thermal-Hydrologic Mechanism for Rainfall-Triggered Collapse of Lava Domes" (2004). School of Geosciences Faculty and Staff Publications. 902.
https://digitalcommons.usf.edu/geo_facpub/902