Geochemical approach to the Bou Hadjar hydrothermal system (NE Algeria)

The Bou Had jar low-temperature hydrothermal system is located in northeast Algeria. The four main thermal springs that are the subject of the study emerge with temperatures between 32 and 60°C from allochthonous formations. The reservoir temperature has been estimated from chemical compositions by utilizing simultaneously the silica, gas and sulfate-water oxygen isotope geothermometers, fluid-mineral equilibrium calculations, and a mixing model. According to these thermometric methods, the most probable subsurface temperature is in the range 75-106°C. The mixing model suggests a temperature of 125°C for the parent water.