东濮凹陷文33断块沙二下亚段浅水三角洲沉积特征

Sedimentary Characteristics of Shallow Water Delta in the Lower Member of Sha 2 Formation in W33 Fault Block

针对文南油田文33断块沙二下亚段油藏储层沉积微相展布特征认识不清、开发效果差、开发方案的部署及调整难度大等问题,笔者综合利用研究区的地质、测井等资料,通过岩石成分、结构、泥岩颜色、沉积构造及测井响应等沉积相标志综合分析,再结合研究区区域沉积背景,精细刻画了沙二下亚段浅水三角洲沉积特征,剖析了沉积微相的展布规律。结果表明,文33断块沙二下亚段浅水三角洲由于其湖水较浅,河流营力起主导作用,储层以条带状展布的水下分流河道砂体为主,其次是薄层水下分流河道侧翼和席状砂,河口坝欠发育;储层测井响应存在4个大类、10个亚类的曲线形态特征;最后,根据沉积微相的展布特征建立沙二下亚断的沉积相模式,从而为油田下一步挖潜提供地质依据。

In view of the problems such as unclear understanding of the distribution characteristics of sedimentary microfacies, poor development effect, difficult deployment and adjustment of development scheme, etc. Based on the geological and logging data of the study area, through the comprehensive analysis of sedimentary facies markers such as rock composition, structure, mudstone color, sedimentary structure and logging response, and combined with the regional sedimentary background of the study area, this paper finely depicts the sedimentary characteristics of shallow water delta in the lower sub member of shahejie-2 and analyzes the distribution law of sedimentary microfacies. The results show that the shallow water delta in the lower ES2 sub member of Wen 33 fault block is dominated by river forces due to its shallow lake water. The reservoir is dominated by banded underwater distributary channel sand body, followed by thin underwater distributary channel flank and sheet sand, and the estuary bar is underdeveloped. There are 4 categories and 10 subclasses of curve morphological characteristics in reservoir logging response. Finally, according to the distribution characteristics of sedimentary microfacies, the sedimentary facies model of the lower sub fault of Shahejie-2 is established, so as to provide geological basis for further tapping the potential of the oilfield.