论文详情
实际地下介质的复杂多样对地震探测技术提出严峻的挑战。黏弹性介质理论的发展及其应用,使得波场衰减信息的利用成为地下油气储层预测的重要技术之一。在概要回顾介质非弹性吸收衰减的一些经典黏弹性模型、黏弹孔隙介质理论和黏弹各向异性理论的基础上,重点介绍了介质中地震波衰减机理的研究进展、衰减各向异性以及强衰减介质理论的提出和发展现状;通过数值模拟对比强调了强衰减模型介质中地震波的衰减特征,指出了强衰减模型综合考虑介质的多种物理因素建立耗散系数来描述地震波黏滞衰减特征的有效性。认为:由于衰减机制研究尚不完善,波场强衰减是值得攻关研究的重要方向,但需要大量岩石物理实验的支撑,并充分结合流体流动机制和各向异性理论建立一般性的衰减介质理论。
The complexity and diversity of the underground media and the increasingly severe exploration problems require the development of a theoretical framework based on viscoelasticity and the exploitation of information on the attenuation of the seismic wave field.It is expected that this information will become crucial for the prediction of underground oil and gas reservoirs.In this paper,the theoretical approaches based on classic viscoelasticity,visco-poro-elasticity,and anisotropic viscoelasticity were briefly reviewed.Recent advances in the understanding of the mechanism of viscoelastic attenuation and its anisotropy,as well as the behavior of strong-attenuation media,were also highlighted.Then,the attenuation characteristics of seismic waves in strong-attenuation media with different physical properties were simulated and compared.The results of the simulations showed that,by establishing a dissipation coefficient,the strong-attenuation model could effectively reproduce the characteristics of viscous attenuation.The study of the strong attenuation of the wave field is expected to become an important research direction;however,this would require the execution of a large number of rock physics experiments but also an improvement of the viscoelastic theory (by accounting for fluid flow and anisotropy) so as to establish a comprehensive attenuation theory.
国家科技重大专项(2017ZX05018005)、国家自然科学基金项目(U1839208)和中国石油化工股份有限公司研发项目(P18070-5)共同资助。