四川盆地简阳区块须家河组须五段储层特征及储层有效性评价

Reservoir Characteristics and Reservoir Effectiveness Evaluation of Xu 5^th Member of Xujiahe Formation in Jianyang Area, Sichuan Basin

摘要: 四川盆地简阳区块须家河组具有较高的勘探潜力，须五段不仅是一个重要的烃源岩层，还具有显著的成藏潜力。为了明确须五段储层特征，评估其资源潜力，本文基于岩心、铸体薄片、电镜扫描等资料，对研究区须家河组须五段储层特征进行了系统分析，通过测井资料对须五段岩性、裂缝进行识别并建立储层分类标准，开展储层有效性评价。研究表明，1) 须五段发育典型的煤–页–砂岩互层，为特低孔特低渗致密砂岩储层；2) 通过测井资料可以有效识别须五段的不同岩性及裂缝并建立以煤–页–砂岩互层为主的储层分类标准；3) 储层基质孔隙发育差导致产能低下，裂缝发育程度较高的储层具有更高的产能，煤–页–砂岩互层具有较高的产能，有利于天然气的聚集。研究结果能为研究区后续勘探开发提供重要依据。

Abstract: Xujiahe Formation has high exploration potential in Jianyang area, Sichuan Basin. Xu 5^th Member is not only an important source rock, but also has significant reservoir formation potential. In order to clarify the reservoir characteristics of Xu 5^th Member and evaluate its resource potential, this paper systematically analyzes the reservoir characteristics of Xu 5^th Member of Xujiahe Formation in the study area based on core, cast thin section and electron microscope scanning data, identifies lithology and fractures of Xu 5^th Member through logging data, establishes reservoir classification criteria, and carries out reservoir effectiveness evaluation. The results show that: 1) The typical coal-shale-sandstone interlayer developed in Xu 5^th Member is a tight sandstone reservoir with extremely low porosity and permeability; 2) Different lithology and fractures of Xu 5^th Member can be effectively identified by logging data, and a classification standard of reservoirs based on coal-shale-sandstone interlayers can be established; 3) The poor development of reservoir matrix pores leads to low productivity. Reservoirs with higher fracture development have higher productivity, and coal-shale-sandstone interbeds have higher productivity, which is conducive to the accumulation of gas. The research results can provide important basis for subsequent exploration and development in the study area.