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富瑞奥组砂岩中由埋藏成岩作用产生的胶结物分布与渗透率和流体活动有关。砂岩成岩作用与流体活动的相互关系表明了岩石改造主要是碎属矿物、自生矿物与孔隙中的地层水发生反应的结果。埋藏期间地层水优先流经高孔渗砂岩。由于渗透性岩石中矿物直接与大量的孔隙反应水接触,这样单位体积反应水所承担的成岩反应量较小,砂岩中的成岩反应很广泛。同样,高孔渗单元也是成岩矿物最优先的沉淀场所。砂岩中自生矿物分布的非均质性是由于埋藏期间流体优先流动路径的改变及其产生的成岩作用差异所造成的。同期沉积期孔渗值不是特别高的砂岩,因为成岩作用较弱,一般具有很好的储层品质。岩相分析表明砂岩中石英次生加大需要的SiO_2具有外源特征,成岩石英的δ~8O值暗示矿物是从快速上升的地层热水中沉淀出来的。远源陆架相砂岩中石英次生加大最丰富,该相带以页岩为主,而其中的孤立砂体能最大限度地混合先期流体。质量平稳计算表明砂岩中石英加大需要的SiO_2需要几千倍孔隙体积的地层水。砂岩中成岩变化需要的地层水远远高于整个富瑞奥组的地层水,它暗示了地层水的循环是重要而又必须的成岩过程。
The distribution of cements produced by burial diagenesis in the Frio Formation sandstone is related to permeability and fluid activity. The correlation between sandstone diagenesis and fluid activity indicates that the alteration of the rock is mainly caused by the reaction of the fractured mineral and the authigenic mineral with the formation water in the pore. Formation water preferentially flows through high porosity and permeability sandstone during burial. Because the minerals in the permeable rocks are in direct contact with a large amount of pore-reacting water, the volume of diagenetic reaction per unit volume of reaction water is small, and diagenetic reactions in the sandstones are extensive. Similarly, high-permeability units are also the highest sedimentation sites for diagenetic minerals. The heterogeneity of the distribution of authigenic minerals in sandstone is due to the change of the preferential flow path during the burial and the difference of diagenesis. Permeability during the deposition period is not particularly high sandstone, because diagenesis is weak, generally have good reservoir quality. The facies analysis shows that SiO 2 needed for quartz secondary growth in sandstone has extrinsic characteristics. The δ ~ 8O value of diagenetic quartz implies that the minerals are precipitated from rapidly rising hot water. In the distant source shelf sandstone, the quartz secondary enrichment is the most abundant, with the shale as the main phase, and the isolated sand body can maximize the mixing of the precursor fluid. Quality-stable calculations show that quartz in sandstone increases the volume of formation water that requires thousands of times the required volume of SiO 2. The formation water required for diagenetic changes in sandstone is much higher than that of the entire Forui Group, suggesting that the formation water circulation is an important and necessary diagenetic process.