基于主成分分析法去屏蔽的地层尖灭线识别技术及应用——以塔河油田678区不整合面T50屏蔽为例

Application of Seismic Shield Removal of Stratum Pinch-out Line Based on Principal Component Analysis(PCA)--A Case Study of Unconformity Surface T50 in Block 678 of Tahe Oilfield

地层尖灭线的识别与刻画对地层尖灭圈闭的描述极为重要。塔河油田石炭系卡拉沙依组地层尖灭线埋深较大,地震反射层能量较弱,分辨率较低,上覆不整合面T50的强反射隐蔽了地层尖灭线的有效反射信号,使地层尖灭位置很难准确判断。利用主成分分析法去不整合面T50的强屏蔽,使尖灭点信息在地震剖面上更加清晰,从而获得地层尖灭线较精确的位置,使沿其发育的一批地层圈闭边界刻画的更加精确,为地层圈闭类油藏储量的准确计算打下坚实基础。

The identification and characterization of stratum pinch-out line were very important for stratum pinch-out trap description.The buried depth of stratum pinch-out line in Carboniferous Kalashayi Formation was larger,and its seismic reflection energy was weaker with low resolution.On the top of the Carboniferous Kalashayi Formation,there was an unconformity surface T50 with strong seismic reflection,by which the effective reflection signal of stratum pinch-out line was hidden,so it was very difficult to accurately identify the pinch-out position.In this paper,principal component analysis(PCA)method is used to shield the strong seismic reflection signal of unconformity surface T50;therefore the pinch-out point is more clear,and more precise stratum pinch-out line position is obtained for accurately describing the boundary of stratum traps which develops along the stratum pinch-out line.The method provides a solid foundation for accurately calculating the reservoir reserves of stratum traps.