论文部分内容阅读
在薄片、Ｘ衍射、扫描电镜、压汞、阴极发光等研究基础上，对鄂尔多斯盆地葫芦河地区三叠系延长组长４＋５段低渗致密砂岩储层特征进行了研究。认为原始矿物组成和结构、早成岩期的机械压实作用和化学压溶作用、晚成岩期的铁方解石胶结作用等是形成低渗致密砂岩储层的主要因素。根据１８个压汞分析样品１１个孔隙结构变量的聚类分析结果，对研究区长４＋５段储层进行了分类评价。指出该区砂岩储层大多应归入低孔特低渗的Ⅲ类和不能作为有效储层的Ⅳ类。
Based on the study of thin slice, X - ray diffraction, scanning electron microscopy, mercury intrusion, cathodoluminescence and other research, the characteristics of low permeability tight sandstone reservoirs in Chang 4 + 5 section of Triassic Yanchang Formation in the Huluhe area, Ordos Basin were studied. It is considered that the composition and structure of primary minerals, mechanical compaction and chemical pressure-solution during early diagenesis and the iron calcite cementation during late diagenesis are the main factors for the formation of low-permeability tight sandstone reservoirs. Based on the cluster analysis results of 11 pore structure variables of 18 mercury intrusion samples, the 4 + 5 reservoirs in the study area were classified and evaluated. It is pointed out that most of the sandstone reservoirs in this area should be classified into Group Ⅲ with low porosity and low permeability and Class Ⅳ that can not be regarded as effective reservoirs.