Abstract The impact of diagenetic minerals and the characteristics of pore structures on reservoir qualities has been studied separately in the past years. However, the difference in the reservoir quality with different pore structures and having same or similar content of diagenesis minerals has not been ascertained. In this study, based on the core samples derived from Chang 6 member in the Ordos basin, various tests were performed to examine the sandstone diagenesis and investigate the pore structure. The results showed that there were five diagenetic facies by diagenetic and pore structure analyses, and the best reservoir quality rocks were found to have relatively low percentage of illite, carbonate cement, pore-filling chlorite, authigenic quartz, and relatively high proportion of intergranular pores. Smectite-to-illite reaction and chemical compaction were main sources for quartz cementation at 60–120°C, and carbonate content was found to increase toward source rocks. The porosity depth trends significantly affected the diagenetic facies. The diagenetic and the pore structure pathways of various diagenetic facies were reconstructed by integrated petrographic, mineralogical, and pore system data. This study provides insights into the porosity evolution and diagenetic pathways of various diagenetic facies of tight sandstones, and the influence of diagenesis minerals and pore structures on their reservoir quality.

中文翻译：

---

致密砂岩成岩相对储层质量的影响

摘要 近年来，人们分别研究了成岩矿物和孔隙结构特征对储层品质的影响。但尚未确定不同孔隙结构和成岩矿物含量相同或相似的储层质量差异。本研究以鄂尔多斯盆地长6段岩心样品为基础，开展了砂岩成岩作用和孔隙结构等多种试验。结果表明，成岩相和孔隙结构分析结果表明，成岩相有5种，储层质量最好的岩石是伊利石、碳酸盐胶结物、充填绿泥石、自生石英、粒间孔比例相对较低的岩石。 . 蒙脱石-伊利石反应和化学压实是60-120°C石英胶结的主要来源，发现碳酸盐含量向烃源岩增加。孔隙度深度趋势显着影响成岩相。综合岩相、矿物学和孔隙系统数据重建了各种成岩相的成岩和孔隙结构路径。该研究为致密砂岩各种成岩相的孔隙度演化和成岩途径以及成岩矿物和孔隙结构对其储层质量的影响提供了见解。综合岩相、矿物学和孔隙系统数据重建了各种成岩相的成岩和孔隙结构路径。该研究为致密砂岩各种成岩相的孔隙度演化和成岩途径以及成岩矿物和孔隙结构对其储层质量的影响提供了见解。综合岩相、矿物学和孔隙系统数据重建了各种成岩相的成岩和孔隙结构路径。该研究为致密砂岩各种成岩相的孔隙度演化和成岩途径以及成岩矿物和孔隙结构对其储层质量的影响提供了见解。