三肇凹陷卫星油田葡萄花油层水下分流河道的精细刻画

Precise description of underwater distributary channel of Putaohua reservoir in Weixing oil field,Sanzhao sag

为精细表征浅水三角洲前缘分流河道薄窄砂体的展布特征,以三肇凹陷卫星油田葡萄花油层为对象,采用地震沉积学方法,结合地层切片和分频颜色融合技术,开展了水下分流河道砂体形态边界精细刻画,建立了3套以稳定洪泛泥岩为标志层的等时地层格架。研究结果表明:葡萄花油层划分为1个长期旋回、2个中期旋回和13个短期旋回;研究区内水下分流河道多呈顺直状条带状沿南北向展布,河道宽75~1008 m,宽厚比集中在40~95,其规模自葡底至葡顶伴随湖退、湖进过程整体先增后减,低位期宽150~1008 m,湖侵期宽95~630 m,高位期宽65~185 m。

This paper seeks to accurately depict distribution characteristics of underwater distributary channel thin narrow sandbodies in shallow water delta.The study based on the seismic sedimentological method involving finely depicting plane distributions of distributary channel sandstone in the Putaohua reservoir in Weixing oil field,Sanzhao sag comprehensively using the technology of stratal slices and establishing frequency division color fusion.and 3 sets of isochronous stratigraphic frameworks with lake flood face as the marker beds.The results show that the Putaohua reservoir is divided into 1 long-term cycle sequence,2 medium-term cycles,and 13 short-term cycles.The analysis of characterization results of“RGB fusion slices identification and seismic profile verification”shows that the distribution of the underwater distributary channels are characterized by a NW-SE direction in a straight strip with low curvature,with the width from 75 to 1008 m and the concentration of width thickness ratio in 40-95.In the precoess of lake regress and transgression,there occurs an initial increase and a subsequent decrease in the channel scale from the bottom to the top of Putaohua reservoir,with the width from 150 to 1008 m in LST,the width from 95 to 630 m in TST,and the width from 65 to 185 m in HST.