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陕甘宁盆地下奥陶统马家沟组五段为潮坪相碳酸盐岩夹蒸发盐沉积。马五段经历了多期复杂的成岩作用，其中溶蚀作用对马五段影响深刻。首次引用热力学理论对埋藏条件下碳酸盐岩溶蚀作用进行了理论分析和计算。其结果表明碳酸盐岩在埋藏成岩的不同温度压力条件下，酸性介质中溶解反应的吉布斯自由能均为负值，说明反应可自动向方解石、白云石溶解的方向进行，并随着温压的升高溶解的趋势增大，而且白云石溶解的趋势比方解石更大。碳酸盐岩溶蚀作用是受热力学规律支配的自然地质作用。碳酸盐岩溶蚀实验模拟的热力学数学模型对陕甘宁盆地油气田勘探具有重大的理论意义和实际应用价值。
The Lower Member of the Lower Ordovician Majiagou Formation in the Shan-Gan-Ning Basin is characterized by evaporative salt deposition by tidal flat carbonate rocks. The fifth member of Ma has experienced complicated and complicated diagenesis, and the dissolution has a profound influence on the fifth member of Ma. The first reference to thermodynamic theory of buried carbonate rock dissolution under the theoretical analysis and calculation. The results show that Gibbs free energy of dissolution reaction in acid medium is negative under different temperature and pressure of burial diagenesis, indicating that the reaction can be automatically carried out in the direction of dissolution of calcite and dolomite, and with Elevated temperature and pressure increase the tendency of dissolution, and dolomite dissolution trend greater than calcite. Carbonate dissolution is dominated by the laws of thermodynamics. The thermodynamic mathematical model of carbonate erosion experiment has great theoretical significance and practical application value for oil and gas field exploration in the Shaanxi-Gansu-Ningxia Basin.