松辽盆地梨树断陷东南斜坡带营城—沙河子组储层特征及主控因素

Reservoir characteristics and main controlling factors of Yingcheng-Shahezi formations in southeast ramp region of Lishu Fault Depression, Songliao Basin

韩志艳 周卓明 杨昊 宋振响

HAN Zhiyan ZHOU Zhuoming YANG Hao SONG Zhenxiang

中国石化 石油勘探开发研究院 无锡石油地质研究所, 江苏 无锡 214126

Wuxi Research Institute of Petroleum Geology, SINOPEC, Wuxi, Jiangsu 214126, China

松辽盆地梨树断陷下白垩统营城—沙河子组砂岩储层非均质性强，钻探成功率较低。通过岩心观察、薄片鉴定及定量统计、孔渗分析、压汞等研究，认为梨树断陷东南斜坡带营城—沙河子组储层以含砾细砂岩为主，其次为细砂岩、中砂岩，具有粗碎屑、石英含量较低，分选、磨圆较差等组构特征；岩石类型为长石岩屑砂岩、岩屑砂岩、岩屑长石砂岩及少量长石砂岩，长石和岩屑含量高，填隙物以泥质、方解石为主；储层物性较差，非均质性强，整体为特低孔、特低渗储层。储层孔隙类型有原生粒间孔、次生溶孔、裂隙等，以原生孔为主，个别地区以裂隙为主。储层的孔隙发育受沉积环境和成岩作用的控制，晚期构造裂隙作用不可忽视。储层成岩作用类型多样，胶结充填和机械压实作用使原生孔隙大量减少，溶蚀和构造破裂则有效改善了储层的物性；特别是晚期构造裂隙作用，产生了不同类型的裂隙，增加了孔隙空间及渗透性，这可能是东南斜坡带秦家屯、金山等地区形成高产油气田的重要原因之一。

The sandstone reservoirs of the Lower Cretaceous Yingcheng-Shahezi formations in the Lishu Fault Depression of the Songliao Basin have a strong heterogeneity and a low exploration success rate. Through core observation, thin section identification and quantitative statistics, porosity and permeability analysis, mercury intrusion, etc., it was concluded that the Yingcheng-Shahezi formations in the southeast ramp of Lishu Fault Depression are dominated by pebbly sandstones, followed by fine-grained and medium-grained sandstones, with low contents of coarse debris and quartz, and low compositional and structural maturities. The main components are feldspathic lithic sandstones, lithic sandstones, and lithic feldspar sandstones, with a small amount of feldspar sandstones. Feldspars and rock debris are in high content, and the interstitial material is mainly argillaceous and calcite. The Yingcheng-Shahezi formations have an ultra-low porosity and an ultra-low permeability with a strong heterogeneity. They consist of primary intergranular pores, secondary dissolved pores and fissures, mainly primary pores, and fractures in some areas. The pore development of reservoirs is controlled by sedimentary environment and diagenesis, and the role of late tectonic fractures cannot be ignored. The primary pores were greatly reduced by cementation and mechanical compaction, while dissolution and structural rupture effectively improved the physical properties of the reservoir. In particular, the late tectonic fissures produced different types of fractures and increased porosity and permeability, which may be one of the important reasons for the formation of high-yield oil and gas fields in the Qinjiatun and Jinshan areas of the southeast ramp.

中国石化科技开发部项目“梨树断陷基岩油气藏勘探潜力及区带评价”（P14041）资助。

https://doi.org/10.11781/sysydz201803345