【摘要】 详细研究了射线追踪、层析反演方法原理以及层析反演数值求解算法,提出了利用大炮初至直接建立初始地震模型,由小折射和微测井进行约束的层析反演近地表速度模型的处理流程,提出了基于多次回溯的高精度快速射线追踪算法和层析反演数值求解算法。采用双重网格技术提高正演模拟计算精度和层析反演的成像质量,另外,充分考虑多种质量控制方案,确保最终的反演速度模型精确。设计了10种不同地表地质条件的理论模型,进行模型试算,并在实际生产中应用,理论模型试算和实际资料反演结果证明了本文方法的正确性。更多还原

【Abstract】 A detailed study of ray tracing,tomographic inversion method and numerical tomographic inversion algorithm were performed and,on such a basis,the method of using first arrival of shot to directly establish the initial seismic model was put forward.In addition,the tomographic inversion of near-surface velocity model process flow with reference to the refraction and logging and the high-precision rapid ray tracing method by multi-retracing and SIRT tomographic inversion were also suggested.The double grid technology was employed to improve modeling simulation accuracy and tomographic inversion imaging quality and,what is more,the multiple quality control plans were fully considered to ensure the precision of the final inversion velocity model.The ray tracing,tomographic inversion,graphics display and some other programs were developed,10 different theoretical surface geological conditions were designed,the theoretical model was tested,and seismic data from Shengli,Sichuan and some other areas were studied.The results of tomographic inversion calculation and actual data inversion prove the correctness of the theoretical research.更多还原