MODELING OF ROCK ALTERATION DUE TO COUPLED HEAT AND MASS-TRANSPORT

A three-dimensional computer model is presented for studying the inter action of heat and mass transport regarding the temporal and spatial e volution of sandstones. The model simulates coupled heat and reactive mass transport in porous rocks. In general, mineral solubilities in wa ter are low. Therefore, large fluid volumes are required to flow throu gh the rock to explain observed mineral cements in sandstones. Besides mass transport, pore fluids transport heat which modifies rock temper atures. Very high flow rates result in strong temperature modification s and, therefore, enhance diagenesis. Low flow rates often cannot acco unt for observed cementation. The model results show the effect of adv ective, convective and conductive heat transport on temperature and di agenetic evolution of sandstones for two different flow systems in a s imple geological environment.