河控三角洲水下分流河道砂体储集层构型精细分析——以扶余油田探51区块为例

An in-depth analysis of reservoir architecture of underwater distributary channel sand bodies in a river dominated delta:A case study of T51 Block,Fuyu Oilfield

基于'模式拟合、动态验证'的研究思路,结合密井网区10口取心井、257口井测井资料及近10年的生产动态资料,对松辽盆地扶余油田探51区块泉四段扶余油层三角洲前缘水下分流河道储集层进行分析,探究水下分流河道储集层内部构型单元的空间展布特征及识别标志。结果表明:研究区目的层单河道砂体宽度为300～500 m,其识别标志分别为:河道间沉积、邻井砂体高程差异、河道砂体厚度差异、相邻砂体的'厚—薄—厚'组合;单河道砂体内部4级构型界面的倾角为0°～2°。明确了水下分流河道储集层中单河道砂体及单河道砂体内部增生体的测井响应特征及识别方法,建立了研究区目的层水下分流河道砂体的三维构型模型,为全区水下分流河道砂体解剖提供了定量、可靠的地质模式。

Guided by the concept of ＂model fitting, dynamic validation＂, and based on the data of 10 coting wells, 257 logging wells, and the production performance in the dense spacing area during the past ten years, the underwater distributary channel sand reservoir in Klq4 of T51 Block, Fuyu Oilfield, Songliao Basin, was analyzed to examine the spatial distribution and identification marks of the architectures within the reservoir. Results indicated that the single channel sand body is 300-500 m wide and can be identified by such marks as inter-channel sediments, sand elevation difference between wells, difference of channel sand thickness, and ＂~tick-thin-thick＂ sands association; the dip angle of the fourth-order interface is 00-2~. Besides, the logging response characteristics and identification method of single channel sand bodies and their interior accreted bodies were defined for the reservoir. A 3D architecture model is established for the underwater distributary channel reservoir in the study area, providing a quantitative and reliable geological model for analysis of underwater distributary channel sands in the whole area.