密度和刚度线性变化对非均匀地壳层中扭转表面波传播的影响

S·古普塔; S·K·维施瓦卡尔玛; D·K·玛里; S·昆杜

doi:10.3879/j.issn.1000-0887.2012.10.002

密度和刚度线性变化对非均匀地壳层中扭转表面波传播的影响

doi: 10.3879/j.issn.1000-0887.2012.10.002

印度矿业学院应用数学系, 丹巴德 826004, 贾坎德邦, 印度

详细信息

中图分类号: O347.4⁺⁴
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出版历程
- 收稿日期: 2011-11-15
- 修回日期: 2012-04-07
- 刊出日期: 2012-10-15

Influence of Linearly Varying Density and Rigidity on Torsional Surface Waves in an Inhomogeneous Crustal Layer

Department of Applied Mathematics, Indian School of Mines, Dhanbad 826004, Jharkhand, India

摘要

摘要: 研究了覆盖在非均匀半无限空间上的非均匀地壳层中，扭转表面波传播的可能性．地壳层的非均匀性随着厚度线性变化，非均匀半无限空间的非均匀性表现为3种类型，即指数型、二次型和双曲型．采用封闭形式，可以分别推导出上述3种类型非均匀性的色散方程．对于覆盖在半空间上的同一地壳层，色散方程与经典案例的方程一致．研究发现，随着非均匀地壳层中密度线性变化的非均匀参数的增大，相速度减小，而由刚度引起的非均匀因素对相速度的影响相反．
- 扭转波 /
- 相速度 /
- 地壳层 /
- 指数型 /
- 二次型 /
- 双曲型
Abstract: The possibility of propagation of torsional surface wave in an inhomogeneous crustal layer over an inhomogeneous half space was disscussed. The layer had inhomogeneity which varied linearly with depth whereas the inhomogeneous half space exhibited inhomogeneity of three types namely exponential, quadratic and hyperbolic discussed separately. Dispersion equation was deduced for each case in a closed form. For a layer over a homogeneous half space, the dispersion equation agreed with the equation of classical case. It is observed that the inhomogeneity factor due to linear variation in density in the inhomogeneous crustal layer decreases the phase velocity as it increases, while the inhomogeneity factor in rigidity has the reverse effect on phase velocity.
- torsional waves /
- phase velocity /
- crustal layer /
- exponential /
- quadratic /
- hyperbolic

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参考文献(23)

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