Geodesy and Gravity/Tectonophysics
Numerical models of caldera deformation: Effects of multiphase and multicomponent hydrothermal fluid flow
Article first published online: 24 APR 2009
Copyright 2009 by the American Geophysical Union.
Journal of Geophysical Research: Solid Earth (1978–2012)
Volume 114, Issue B4, April 2009
How to Cite
2009), Numerical models of caldera deformation: Effects of multiphase and multicomponent hydrothermal fluid flow, J. Geophys. Res., 114, B04411, doi:10.1029/2008JB006151., , , and (
- Issue published online: 24 APR 2009
- Article first published online: 24 APR 2009
- Manuscript Accepted: 14 JAN 2009
- Manuscript Revised: 31 DEC 2008
- Manuscript Received: 8 OCT 2008
 Ground surface displacement (GSD) in large calderas is often interpreted as resulting from magma intrusion at depth. Recent advances in geodetic measurements of GSD, notably interferometric synthetic aperture radar, reveal complex and multifaceted deformation patterns that often require complex source models to explain the observed GSD. Although hydrothermal fluids have been discussed as a possible deformation agent, very few quantitative studies addressing the effects of multiphase flow on crustal mechanics have been attempted. Recent increases in the power and availability of computing resources allow robust quantitative assessment of the complex time-variant thermal interplay between aqueous fluid flow and crustal deformation. We carry out numerical simulations of multiphase (liquid-gas), multicomponent (H2O–CO2) hydrothermal fluid flow and poroelastic deformation using a range of realistic physical parameters and processes. Hydrothermal fluid injection, circulation, and gas formation can generate complex, temporally and spatially varying patterns of GSD, with deformation rates, magnitudes, and geometries (including subsidence) similar to those observed in several large calderas. The potential for both rapid and gradual deformation resulting from magma-derived fluids suggests that hydrothermal fluid circulation may help explain deformation episodes at calderas that have not culminated in magmatic eruption.