STUDY OF SIMULATION EXPERIMENT FOR CARBONATE ROCKS DISSOLUTION IN BURIAL DIAGENETIC ENVIRONMENT

Under the condition of the same pressure and different temperature where acetic acid,CO₂ and H₂S as solution,respectively,the experiments of dissolution for different type carbonate rocks have been performed the ability of dissolution of the dolostone is lower compared with the limestone.And the ability of dissolution of transitional type carbonate rocks is between limestone's and dolostone's.The results show that the ability of dissolution of dolomite is lower than calcite.Under the condition of the same temperature and different pressure where acetic acid as solution,when pressure is between 0.2 and 30MPa,the results show that the ability of dissolution of dolostone is lower than limestone.However,when pressure is 50MPa,the dissolution abilities of samples obviously increase.The increased extent is characterised that dissolution intensity of the dolostone is most large,intensity of limestones is most low and intensity of algal limestone is between dolostones and limestones.Based on previous results presumed when pressure increases,the dissolution intensity of dolostones is more than the limestone.However,the microcrystalline limestone dissolution of different particle size indicates that the dissolution rate of large particle size is 1.49 times larger than that small size.All these show that the dissolution extent depends on the main factors of specific surface area caused by contaction of fluid and minerals besides of mineral composition.