Chemistry and Physics of Minerals and Rocks/Volcanology
Hydrothermal fluid flow and deformation in large calderas: Inferences from numerical simulations
Article first published online: 24 FEB 2007
Copyright 2007 by the American Geophysical Union.
Journal of Geophysical Research: Solid Earth (1978–2012)
Volume 112, Issue B2, February 2007
How to Cite
2007), Hydrothermal fluid flow and deformation in large calderas: Inferences from numerical simulations, J. Geophys. Res., 112, B02206, doi:10.1029/2006JB004689., , and (
- Issue published online: 24 FEB 2007
- Article first published online: 24 FEB 2007
- Manuscript Accepted: 17 OCT 2006
- Manuscript Revised: 5 OCT 2006
- Manuscript Received: 10 SEP 2006
- numerical simulation;
- ground surface displacement;
 Inflation and deflation of large calderas is traditionally interpreted as being induced by volume change of a discrete source embedded in an elastic or viscoelastic half-space, though it has also been suggested that hydrothermal fluids may play a role. To test the latter hypothesis, we carry out numerical simulations of hydrothermal fluid flow and poroelastic deformation in calderas by coupling two numerical codes: (1) TOUGH2 [Pruess et al., 1999], which simulates flow in porous or fractured media, and (2) BIOT2 [Hsieh, 1996], which simulates fluid flow and deformation in a linearly elastic porous medium. In the simulations, high-temperature water (350°C) is injected at variable rates into a cylinder (radius 50 km, height 3–5 km). A sensitivity analysis indicates that small differences in the values of permeability and its anisotropy, the depth and rate of hydrothermal injection, and the values of the shear modulus may lead to significant variations in the magnitude, rate, and geometry of ground surface displacement, or uplift. Some of the simulated uplift rates are similar to observed uplift rates in large calderas, suggesting that the injection of aqueous fluids into the shallow crust may explain some of the deformation observed in calderas.