- Editors' Suggestion
- Open Access
- Access by Xinjiang University
Experiments on buoyancy-driven instability ahead of a dissolution front in a porous rock
Phys. Rev. Fluids 10, 024001 – Published 6 February, 2025
DOI: https://doi.org/10.1103/PhysRevFluids.10.024001
Abstract
Fluid-rock reactions are of great interest in many engineered geological storage and disposal systems where the long term integrity of the system is key, and where fluid seepage through a permeable rock may lead to reaction and convective transport of material through the formation. If an unsaturated fluid displaces formation fluid in equilibrium with a reactive porous medium, a reaction front develops, across which the invading fluid becomes saturated with the soluble matrix material. Depending on the composition of the invading fluid, it may initially be less dense than the formation fluid, but following reaction it may become denser than the formation fluid. If the invading fluid displaces the formation fluid downwards through the porous layer, the reaction front may then be stabilized by buoyancy, but a Rayleigh-Taylor type instability can develop at the interface between the reacted fluid and the original formation fluid ahead of the reaction front. We present a series of new analog experiments of this process by injecting aqueous sugar solutions into a porous layer containing saturated salt solution, salt powder, and glass ballotini. As an analog of a reaction front, a dissolution front develops as the aqueous sugar solution dissolves the salt powder and becomes denser than the saturated salt solution. The buoyancy instability then leads to a growing finger interface. If the buoyancy speed of the fluid, , is smaller than , where the speed of the advancing fluid-fluid front is and the speed of the dissolution front is then the instability grows as if the system were unconfined. However, if , then the supply of fluid at the dissolution front limits the growth of the instability. We present an idealised model for the speed of the non-linear buoyancy-driven fingers, and we consider the implications of our results for the long term integrity of a number of geological storage systems.
Physics Subject Headings (PhySH)
Article Text
References (18)
- O. M. Phillips, Flow and Reactions in Permeable Rocks (Cambridge University Press, Cambridge, UK, 1991).
- A. W. Woods, Geothermal power and heat storage, in Flow in Porous Rocks: Energy and Environmental Applications (Cambridge University Press, Cambridge, UK, 2014), pp. 227–261.
- N. Yanagisawa, I. Matsunaga, H. Sugita, M. Sato, and T. Okabe, Temperature-dependent scale precipitation in the hijiori hot dry rock system, japan, Geothermics 37, 1 (2008).
- E. Gunnlaugsson, H. Ármannsson, S. Thorhallsson, and B. Steingrímsson, Problems in geothermal operation - scaling and corrosion, in Short Course VI on Utilization of Low- and Medium-Enthalpy Geothermal Resources and Financial Aspects of Utilization (United Nations University Geothermal Training Programme, 2014), https://geocom.geonardo.com/assets/elearning/3.3.UNU-GTP-SC-18-19.pdf.
- W. Kruger and R. Latypov, Magmatic karst reveals dynamics of crystallization and differentiation in basaltic magma chambers, Sci. Rep. 11, 7341 (2021).
- F. Gutiérrez, A. Cooper, and K. Johnson, Identification, prediction, and mitigation of sinkhole hazards in evaporite karst areas, Envrionmental Geology 53, 1007 (2008).
- E. Shalev, V. Lyakhovsky, and Y. Yechieli, Salt dissolution and sinkhole formation along the dead sea shore, J. Geophys. Res.: Solid Earth 111, B3 (2006).
- Y. Liu, S. Jin, Q. Cao, and W. Zhou, Tertiary hydrothermal activity and its effect on reservoir properties in the xihu depression, east china sea, Petroleum Science 16, 14 (2019).
- T. Menand, A. Raw, and A. W. Woods, Thermal inertia and reversing buoyancy in flow in porous media, Geophys. Res. Lett. 30, 2002GL016294 (2003).
- S. E. Ingebritsen, S. Geiger, S. Hurwitz, and T. Driesner, Numerical simulation of magmatic hydrothermal systems, Rev. Geophys. 48, RG1002 (2010).
- J. G. Newton, Development of Sinkholes Resulting from Man's Activities in the Eastern United States, Circular 968 (U.S. Geological Survey, 1987), https://pubs.usgs.gov/circ/1987/0968/report.pdf.
- G. M. Brown, The layered ultrabasic rocks of rhum, inner hebrides, Philos. Trans. R. Soc. London, Ser. B 240, 1 (1956).
- R. Didonna, F. Costa, H. Handley, S. Turner, and J. Barclay, Dynamics and timescales of mafc–silicic magma interactions at soufrière hills volcano, montserrat, Contrib. Mineral. Petrol. 177, 28 (2022).
- Radioactive Waste Management Ltd, Geological disposal generic environmental safety case, Disposal System Safety Case Report DSSC/203/01 (Nuclear Decommissioning Authority, 2016), https://assets.publishing.service.gov.uk/media/5a82361e40f0b6230269b6f2/NDA_Report_no_DSSC-203-01_-_Geological_Disposal_-_Generic_Environmental_Safety_Case_-_Main_Report.pdf.
- P. Bohuon, M. Le Maguer, and A. L. Raoult-Wack, Densities and viscosities of ternary systems of nacl-sucrose-water, J. Chem. Eng. Data 42, 266 (1997).
- R. M. Holt and D. W. Powers, valuation of halite dissolution at a radioactive waste disposal site, andrews county, texas, Geol. Soc. Am. Bull. 122, 1989 (2010).
- S. E. Pringle and R. J. Glass, Double-diffusive finger convection: Influence of concentration at fixed buoyancy ratio, J. Fluid Mech. 462, 161 (2002).
- C. Cooper, R. J. Glass, and S. W. Tyler, Experimental investigation of the stability boundary for double-diffusive finger convection in a hele-shaw cell, Water Resour. Res. 33, 517 (1997).
