【摘要】 叠前深度偏移是解决库车山地复杂构造准确成像的较好方法,但其对速度精度要求较高,在地震数据信噪比低、速度模型不准的情况下,叠前深度偏移成像质量并不理想,因此,叠前时间偏移仍是认识该区构造的重要手段。通过实际资料处理,认为克希霍夫叠前时间偏移技术在库车山地的应用的关键点是起伏地表地震旅行时的估算和求取准确的均方根速度:前者包括从近地表面开始计算每个成像点的t0时间和该成像点道集中炮检点的旅行时;后者主要是精细的速度分析和速度扫描。该方法在库车山地实际资料处理中取得了较好的成像效果,值得进一步推广应用。更多还原

【Abstract】 Prestack deep migration(PDM) as the best way to solve the accurate imaging of complex structures in Kuqa mountain land requires high precision in velocity,so the imaging quality of PDM is normally unsatisfactory in the condition of an inaccurate velocity model and low S/N.It is indispensable for using prestack time migration(PTM) data to guide the structural understandings in this area.The key point of Kirchhoff prestack time migration technology applied to Kuqa mountain land is the estimation of seismic travel time and the accurate solution of root-mean-square velocity on the relief surface.The former includes calculation of the time t0 of each imaging point and the travel time of shot-to-geophone points in the imaging point’s gather from the near-surface,and the latter includes the fine velocity analysis and the velocity scanning.By using this method,good imaging effects are obtained in actual seismic data processing from Kuqa mountain land,and worth further researching and generalizing.更多还原