通过采用岩心观察、薄片鉴定、扫描电镜观察、压汞实验等技术手段,利用储层特征定性描述与成岩改造孔隙量定量表征相结合的研究方法,对红层储层沉积成岩特征和储集空间成因类型进行研究,明确红层储层物性的主控因素.结果表明:红层沉积时期发育冲积扇—洪水-漫湖—盐湖沉积体系;储层主要发育在冲积扇、漫湖坪、漫湖席状砂、漫湖滩坝中,储层中主要发育原生粒间孔、残余粒间孔、粒间溶孔、粒内溶孔等4类孔隙;红层储层受控于沉积作用和成岩作用,其中沉积作用表现为岩石粒径和成熟度对储层孔隙结构和物性的影响,而成岩作用对储层物性起到明显的控制作用,压实减孔量主要受控于深度和填隙物含量控制,胶结减孔量受控于早期碱性成岩环境的强弱,溶蚀增孔量受控于中晚期酸性成岩环境的强弱,离湖盆中心越近,胶结减孔量、溶蚀增孔量越高,反之则越低.%Comprehensive analyses were implemented to investigate the sedimentary diagenetic characteristics and reservoir space genetic types of red beds, utilizing core observation, thin section identification, scanning electron microscope observa-tion and mercury injection experiment. A qualitative description of reservoir characteristics was combined with the quantita-tive characterization of porosity due to diagenetic modification. In addition, the main factors controlling the physical proper-ties of red beds were explored. It is demonstrated that during the deposition of red beds, the main environment was the alluvi-al fan-flooded lake-salty lake sedimentary system, and reservoirs were mainly developed in the alluvial fan, flooded lacustrine flat, flooded lacustrine sheet sandstone, and flooded lacustrine beaches and bars, in which the dominant pores are primary intergranular pores, residual intergranular pores, intergranular dissolution pores, and intragranular dissolution pores. Sedi-mentation and diagenesis are identified to be the main controlling factors:the former controlled the pore structure and physi-cal properties through influencing the grain size and maturity of red beds, while the latter determined the reservoir properties by compaction, cementation and dissolution. To be specific, the porosity decrease due to compaction was controlled by burial depth and fillings, the porosity loss due to cementation was determined by the eogenetic alkaline diagenetic environment, and the porosity increase due to dissolution was attributable to the acidity of the telogenetic sedimentary environment. Lastly, the porosity loss due to cementation and the porosity increase due to dissolution were enhanced in the lacustrine center.
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