摘要
地震数据是典型的带限信号,这限制了传统高频射线理论在其偏移处理中的应用。本文构建了一种适用于横向各向同性(TI)介质的带限射线束传播算子,并应用于射线束偏移。在局部平面波近似下构建了带限射线追踪算法,并将该算法扩展到TI介质。在带限中心射线基础上引入旁轴近似展开,构建适用于TI介质的带限射线束传播算子,将该带限射线束传播算子应用于各向异性介质射线束偏移。该传播算子在保持射线类方法高效灵活优点的基础上,兼具波动类波传播算子能够描述带限波场传播的特性。数值实验表明,各向异性带限射线束改善了盐丘等复杂构造与各向异性区域的照明,提高了偏移成像剖面和角度域共成像点道集的质量。
Seismic data are typical band-limited signals that limit the application of conventional high-frequency ray theory in seismic data processing and migration.In this paper,a band-limited beam propagation operator for TI media is developed,and it is applied to beam migration.Firstly,a band-limited ray tracing algorithm is developed under the local plane wave approximation,and this algorithm is extended to TI case.Then,the paraxial approximation is introduced to extrapolate the central bandlimited ray to a band-limited beam propagator.Finally,the band-limited beam propagator is applied to TI beam migration.The operator can describe the characteristics of band-limited seismic wave propagation;meanwhile it inherit the advantages of ray based propagators,i.e.,efficient and flexible.Numerical experiments show that the TI bandlimited beams improve the illumination of complex salt structures and anisotropic areas,and enhance the quality of the imaging profile and generated angle domain common imaging gathers.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2018年第2期297-303,310,共8页
Oil Geophysical Prospecting
基金
国家科技重大专项(2016ZX05026001-001)
国家自然科学基金项目(41604092)
中国石化国家重点实验室开放基金项目(3355000614FW20990026)联合资助
