低渗透油藏“甜点”成藏模式及主控因素分析——以松辽盆地南部扶杨油层为例

通过对松辽盆地南部中央坳陷区扶杨油层的地质解剖。将低渗透油藏“甜点”的成藏模式分为“直排型”和“断层供油型”2种类型。综合分析认为烃源岩、储集层、沉积物源和断层是“甜点”形成的主要控制因素。优质烃源岩发育提供充足油源，超压为排烃动力，烃源岩与储集层广泛紧密接触；泉四段Ⅰ砂组和Ⅲ砂组合油性好于Ⅱ砂组和Ⅳ砂组。Ⅰ砂组顸薄砂岩厚，Ⅱ-Ⅳ砂组砂体由断层沟通油源；储集层厚度大于3m，主要沉积相为主河道和河漫滩相；主河道砂体聚油、通榆物源主河道砂体含油性好于保康物源主、次河道砂体。

Accumulation patterns and controlling factors of "Sweet Point" in low permeability reservoir :A case study from Fuyang reservoir in southern Songliao Basin

Based on the geologic dissection of Fuyang reservoir in southern Songliao Basin, the accumulation pattern of ＂sweet point＂ is divided into ＂Directly expulsion＂ type and ＂Fault supply oil＂ type. The source rocks, reservoir, sedimentary source and fault are considered as the main controlling factors for the formation of ＂sweet point＂. High quality source rocks supply abundant oil sources, and anomalous pressure is the major driving force for hydrocarbon expulsion. Oiliness of the sand group Ⅰ and Ⅱ is better than that of group Ⅲ and Ⅳ in Quan 4 member. The reservoir thickness is more than 3 meters. The main sedimentary facies are fiver channel and flood land. The oiliness of the main fiver channel sand body in Tongyu sedimentary source is better than in Baokang sedimentary source.