作　　者： (李立平）; (何兵寿）;

机构地区： 中国海洋大学海洋地球科学学院,青岛266100 青岛海洋科学与技术国家实验室海洋矿产资源评价与探测技术功能实验室,青岛266071 中国海洋大学海底科学与探测技术教育部重点实验室,青岛266100

出　　处： 《地球物理学进展》 2017年第4期1584-1590,共7页

摘　　要： TTI(Tilted Transversely Isotropic)各向异性是对地下岩石中广泛存在的规则发育的裂缝和层理的一种有效的弹性近似,基于TTI介质的地震波数值模拟技术是分析地震波在复杂各向异性介质中的传播机理的有效工具.同时,高精度的数值模拟算法也能为后续的逆时偏移技术提供重要的技术支撑.由于TTI介质中地震波方程的弹性参数众多且变化复杂,常规有限差分技术在解决TTI介质正演模拟问题时往往会产生严重的数值频散现象,降低了数值模拟精度.通量校正传输(FluxCorrected Transport,FCT)技术能够有效地压制由空间离散产生的数值频散.本文将FCT技术用于TTI介质中弹性波方程的交错网格高阶精度差分正演,在数值模拟过程中通过对波场进行漫射和反漫射校正实现了空间网格频散的压制.模型模拟结果表明,与常规有限差分算法相比,本文算法能够有效的压制大网格条件下的数值频散,提高模拟精度. TTI anisotropy is an effectively elastic approximate to the rule growth fissure and stratification.Seismic wave numerical simulation based on the TTI media is an effective way to analysis propagation mechanisms of seismic wave in complex anisotropic media.High-precision numerical simulation algorithm provides important technical support to reverse time migration.Owing to the elastic parameter of TTI media elastic wave equation are numerous and complex,conventional finite-difference technique have seriously numerical dispersion phenomenon in the forward modeling of TTI media and decrease the numerical simulation accuracy.FCT can suppress numerical dispersion caused by space discrete.The paper applied FCT to the elastic wave staggered grid high-order accuracy difference forward modeling in TTI media,make diffusion and antidiffusion to wave field in the process of numerical simulation and suppress the numerical dispersion caused by large grid.The result of model simulation shows that compared with conventional finite difference method,algorithm in this paper can suppress numerical dispersion in the large grid and improve simulation accuracy.

关 键 词： 介质 有限差分 交错网格 数值频散 通量校正传输