Stratabound Rayleigh convection observed in a 4D hydrothermal reactive transport model based on the regional geological evolution of Allermöhe (Germany)

We investigated stratabound Rayleigh convection as a means of transport for leaching of solutes from salt diapirs, their dissipation into the Rhaetian sandstone aquifer and subsequent precipitation of anhydrite with resulting cementation. Reactive transport modelling has been conducted in the context of the recent structure of the Allermohe site and its palaeogeological development. Resulting flow fields depict large (km-scale) stratabound Rayleigh convection. However, our simulations show the vicinity of the Allermohe well as a potential area of anhydrite dissolution in contrast to field observations, with precipitation concentrated elsewhere.

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