CO2流体对含片钠铝石砂岩改造作用的实验研究

不同温度（100℃，200℃和300℃）下CO_{2流体对含片钠铝石砂岩的改造作用研究显示:随着温度的升高，砂岩的溶蚀、溶解程度逐渐增强，样品中片钠铝石的稳定性逐渐减弱。同时，各温度下样品表面均有一水软铝石放射状集合体沉淀。200℃时，随着片钠铝石的溶解有自生菱铁矿生成，300℃时样品局部有绿泥石沉淀。100℃下片钠铝石的微弱溶解及200℃下菱铁矿的形成表明，在地层条件下以碳酸盐矿物形式捕获的CO2，不会由于CO2的二次注入而重新释放。}

Study on the Dawsonite Sandstones Reformation with CO2 Fluid

Based on the study on the reformation of Dawsonite sandstones with CO₂ fluids at different temperature (100℃, 200℃ and 300℃) and different the CO₂/H₂O/sandstone systems in inclosed containers, it is suggested that the corrosion intensity of dawsonite sandstone will gradually be enhanced as the temperature increases. At the same time, the SEM study shows that gibbsite occurs on the sample surface. At 200 ℃, as dawsonite sandstone is being dissolved authigenic siderite forms. At 300℃, chlorite deposit on parts of the sample surface. The weak solution of dawsonite sandstone at 100℃ and the formation of siderite at 200℃ illuminate that CO₂ being in carbonates in the strata can not be released when CO₂ phase is adding to the system.