Geothermal convection in carbonate platforms could drive massive dolomitization by supplying mass transport of magnesium over long periods and at temperatures high enough to overcome kinetic limitations. Reactive-transport simulations based on Enewetak Atoll show dolomitization in a thin band at a permeability contrast near the base of the platform, which is consistent with field observations of dolomitized Eocene deposits. Dolomitization is predicted at approximately 6% per My at temperatures of 45–60°C, and complete dolomitization could be accomplished in ∼16 My. Calcium enrichment of pore fluids and upward transport of these fluids is established early, prior to 30 ky.
Additional publication details
Geothermal convection: a mechanism for dolomitization at Enewetak Atoll?
Elsevier Science Publishers B.V.
Larger Work Title:
Journal of Geochemical Exploration
Geofluids III - 3rd International Conference on Fluid Evolution, Migration and Interaction in Sedimentary Basins and Orogenic Belts