4 research outputs found
Numerical Modeling of Supercritical âOut-Saltingâ in the âAtlantis II Deepâ (Red Sea) Hydrothermal System
Supercritical water behaves close to that of a non-polar fluid and its ability to dissolve salt ions is very low. In rifting locations world-wide, where hot vents occur, it has been shown that seawater attains supercritical conditions. We therefore anticipate that circulation of seawater in hydrothermal systems passing through regions of the supercritical domain results in spontaneous precipitation of salt particles. Thus, the hot âgeysersâ of saturated brines observed in the âAtlantis II Deepâ of the Red Sea could result from re-dissolution of salts accumulated in underground fracture systems. Here we report on an advanced numerical modeling study which demonstrates, for the first time, that there is a forced convection cell where salts precipitate and accumulate. These combined numerical thermodynamic simulations and basin modelling results also demonstrate that hot brines reflux back to surface immediately above the magma chamber located beneath the axis of the rift. Based on this study, we predict that hydrothermal âout-saltingâ is the main cause of dense, warm brines accumulating in the central portion of the Red Sea. Furthermore, the results are relevant for understanding how large volumes of evaporites (salts) accumulate along rifted plate margins