基于层控数据驱动的层间多次波预测与压制方法及其应用

Layer-controlled data-driven method for predicting and suppressing internal multiples and its applications

复杂的火成岩或膏岩层强反射界面产生的层间多次波对一次波有强烈的干涉效应,精准识别层间多次波并对其进行预测和压制是地震资料处理的技术瓶颈之一。常规的叠前数据驱动的层间多次波预测与压制方法需要预测每个反射界面产生的多次波,效果不佳且运算量非常大。为此,提出基于层控数据驱动的层间多次波预测与压制方法,从层间多次波正演模拟出发,分析了对目的层有影响的层间多次波的产生来源和形成的地质条件,再利用井标定的井震匹配情况和构造模型多次波正演模拟记录进行对比确定,将产生多次波的主要反射界面作为层控模型层,从而减少对所有多次波进行预测的运算量,再采用逐层预测和压制的思路,保证预测的层间多次波的有效性,最后,采用保护指定有效地层的最小二乘自适应匹配相减技术进行层面多次波的压制。模拟数据和实际资料的处理结果表明,该方法能够有效预测和压制有影响的层间多次波,从而消除假构造,提高了地层构造、断裂和缝洞型储层的成像精度。

Internal multiples generated by the strong reflection interface of complex igneous rock or gypsum rock strongly interfere with the primary reflection.Accurate identification,prediction,and suppression of these internal multiples are technical bottlenecks in seismic data processing.The conventional pre-stack data-driven method for predicting and suppressing the internal multiples generated by each reflector is inefficient and computationally expensive.Therefore,a layer-controlled data-driven method was proposed to predict and suppress the internal multiples.First,based on internal multiple forward modeling,the generating source and geological conditions of the formation of internal multiples that affect the target zone were analyzed and obtained.Second,the source of the internal multiples was further determined by comparing the calibrated seismic matching conditions with the forward modeled internal multiple.Third,the main generating reflectors of the multiples were considered as a layer-controlled model,and a layer-by-layer prediction and suppression process was adopted to predict the internal multiples and reduce computational cost.Finally,the protected least-squares adaptive subtraction method was used to suppress the multiples.The synthetic and field data test results showed that this method can effectively predict and suppress internal multiples that strongly interfere with the target.This can eliminate false structures and improve the imaging accuracy of stratigraphic structures,fractures,and fracture-vuggy reservoirs.