松辽盆地三肇凹陷东部葡萄花油层高分辨率层序地层模式探讨

 针对三肇凹陷东部葡萄花油层地层对比和划分中存在的不统一现象,依据8口井岩心和1700口井测井资料及地震资料,应用高分辨率层序地层学理论对三肇凹陷东部葡萄花油层进行层序地层学研究,将三肇凹陷东部葡萄花油层划分为2个中期基准面旋回和9个短期基准面旋回;葡萄花油层的地层发育模式为向南地层厚度减薄,葡萄花油层顶上移、底下移,各层渐薄,而非中部缺失或底部缺失的层序地层新格架。中期基准面旋回的转换点位于SSC₄中部,转换点以下为下降半旋回,转换点以上为上升半旋回的地层发育模式,并建立了研究区与三肇凹陷统一的高分辨率层序地层格架。该地层格架的建立为后期油藏开发提供可靠地质依据。

The High Resolution Sequence Stratigraphy Pattern of Putaohua Oil Layer in the East Region of Sanzhao Depression,Songliao Basin

The Putaohua reservoir in the east region of Sanzhao depression is connected to the oil and gas resources in Songliao Basin. Due to the inconsistency about stratigraphic correlation and classification of Putaohua oil layer in the east region of Sanzhao depression, the precise high frequency sequence identification and classification of the reservoir are needed. And a union stratigraphic framework is established. Based on eight well cores and logging and seismic data of 1700 wells, according to the theory of high-resolution sequence stratigraphy sedimentary, the Putaohua oil layer in the east region of Sanzhao depression is studied. The interface and characteristics of each grade base level cycle in the east region of Sanzhao depression, Songliao Basin is systematically analyzed. The oil layer is divided into two medium-term base level cycles and nine short-term base level cycles. On the basis of the analysis on the structural type of short term base level cycles sequence, the development pattern of the Putaohua oil layer in the above area is explored. The stratigraphic model is that the thickness of the formation becomes thin toward the south. The top of the Putaohua oil layer moves up, the bottom of that moves down, and each layer is gradually thinning. It is opposed to the new framework of sequences with the absence of central layer or the bottom. The formation development pattern is that the transition point of the medium-term base level cycle is located at the center of SSC₄. There is a decreased half-cycle below the transition point, and an increased half-cycle above the transition point. In addition, a high resolution sequence stratigraphic framework is established. The framework unifies the study area with the Sanzhao depression, providing the solid geological basis for the sandstone distribution, establishment of distribution pattern of reservoir, the cause identification of mainly monosandbody, and potential oil field further tapping.