四川盆地开江—梁平海槽东侧三叠系飞仙关组鲕滩储层特征及控制因素

通过岩心观察、微观薄片鉴定、扫描电镜等资料，在层序划分基础上对四川盆地开江—梁平海槽东侧飞仙关组的储层特征及控制因素进行了研究。研究结果表明： ①铁山坡—普光地区飞仙关组储层以鲕粒云岩和细粉晶白云岩为主，渡口河—七里北地区以（含砾屑、砂屑、豆粒）鲕粒白云岩为主，鲕粒岩原始结构组分保存更好。②研究区储层具有多期次发育特征，铁山坡—普光地区储层在ssq1，ssq2，ssq3层序均有分布，具有发育早、厚度大、分布面积广的特征，Ⅰ，Ⅱ，Ⅲ类储层均发育；渡口河—七里北地区储层发育在ssq2，ssq3层序，发育较晚、厚度小、分布面积有限，以Ⅱ，Ⅲ类储层为主。③研究区沉积古地貌及海平面升降控制了鲕滩储层发育的期次、厚度等，在ssq1沉积中晚期海平面开始下降时，古地貌高地开始发育鲕滩储层，厚度大，白云石化作用明显。④研究区内陡坡型和缓坡型台缘斜坡带，水体能量的强弱控制了鲕滩沉积物类型，为成岩期溶蚀作用和白云石化作用奠定了物质基础，进而控制了储层的物性和规模。

Characteristics and main controlling factors of oolitic shoal reservoirs of Triassic Feixianguan Formation in eastern Kaijiang-Liangping trough,Sichuan Basin

Based on core observation, micro thin section identification and scanning electron microscope analysis, combined with sequence division, the reservoir characteristics and controlling factors of Triassic Feixianguan Formation in eastern Kaijiang-Liangping trough of Sichuan Basin were studied. The results show that:(1) The reservoirs of Triassic Feixianguan Formation are dominated by oolitic dolomite and fine silty dolomite in TieshanpoPuguang area, and oolitic dolomite(with gravel, sand and bean grains) in Dukouhe -Qilibei area, and the original structural components of oolitic rocks are better preserved.(2) The reservoirs in the study area are characterized by multi-stage development. The reservoirs in Tieshanpo-Puguang area are developed in ssq1, ssq2 and ssq3 sequences, with the characteristics of early development, large thickness and wide distribution area, and type Ⅰ, Ⅱ and Ⅲ reservoirs are developed. The reservoirs in Dukouhe Qilibei area are developed in ssq2 and ssq3 sequences, which are late developed, small in thickness and limited in distribution area, and are dominated by type Ⅱ and Ⅲ reservoirs.(3) Sedimentary palaeogeomorphology and sea-level change control the development stages and thickness of oolitic shoal reservoirs in the study area. When sea-level began to decline in the middle and late stages of ssq1, oolitic shoal reservoirs began to develop in the paleogeomorphic highlands with large thickness and obvious dolomitization.(4) The water energy in steep slope and gentle slope margin slope zones affects the types of oolitic shoal sediments, provides a material basis for diagenetic dissolution and dolomitization, and thus controls the physical properties and scale of the reservoir.