论文部分内容阅读
研究区位于辽河坳陷大民屯凹陷西部,南起沈281井,北至沈299井,东起胜11井,西至大民屯凹陷边界,面积约为300km2。研究区沙四段扇三角洲相扇群状分布,前缘砂砾岩体沉积厚度大,为有利沉积相带。沙三段三角洲、河流相沉积砂体分布相对稳定。沙河街组含油层系主要分布在沙四段和沙三段中下部。近年来,大民屯凹陷主要勘探工作集中在潜山上,古近系勘探少有发现。从沉积学和储层岩石学特征入手,结合常规岩石薄片、铸体薄片、扫描电镜、孔渗分析、压汞实验分析结果,对辽河盆地大民屯凹陷沙河街组沙三段、沙四段储层特征及影响因素进行研究。结果表明,沙四段多为低孔特低渗储层,储集空间为原生孔隙、次生孔隙和裂缝。沙三段储层成分成熟度和结构成熟度相对较高,原生孔隙得到一定保存,储集性能好,发育中孔中-低渗储层。沉积作用、成岩作用、物源区母岩岩性及断裂活动,是导致储层物性复杂化的主要影响因素。
The study area is located in the western part of the Damintun Depression in the Liaohe Depression, from the Shen-281 well to the south and Shen-299 well to the north, Sheng-11 well to the east and to the boundary of the Damintun Depression in the west with an area of about 300 km2. In the study area, the fan-delta fan facies distributes in the Shahejie formation. The sedimentary thickness of the frontal glutenite body is large and is favorable for sedimentary facies belt. Triassic sandstone, river sedimentary sand body distribution is relatively stable. The Shahejie Formation oil-bearing strata are mainly distributed in the middle and lower parts of Sha 4 and Sha 3 sections. In recent years, the major exploration work in the Damintun Depression has been focused on buried hills, with few discoveries made by Paleogene exploration. Based on the characteristics of sedimentology and reservoir petrology, combined with the results of conventional rock slice, cast slice, scanning electron microscopy, pore permeability analysis and mercury intrusion test, the sediment characteristics of Shahejie Formation in Shahejie Formation of Lantian Basin are analyzed. Reservoir characteristics and influencing factors. The results show that most of the Sha 4 Member is a low-porosity and ultra-low permeability reservoir with primary, secondary porosity and fractures. The maturity and structural maturity of the third member of the third member of the Shahejie formation are relatively high, and some primary pores are preserved and the reservoir performance is good. Medium-low permeability reservoirs are developed. Deposition, diagenesis, source rock lithology and fault activity are the main factors that lead to the complicated reservoir physical properties.