Influence of linearly varying density and rigidity on torsional surface waves in inhomogeneous crustal layer

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• 作者：S. Gupta (1) shishir_ism@yahoo.com
  S. K. Vishwakarma (1)
  D. K. Majhi (1)
  S. Kundu (1)
• 关键词：Key words torsional wave – ; phase velocity – ; crustal layer – ; exponential – ; quadratic – ; hyperbolic
• 刊名：Applied Mathematics and Mechanics
• 出版年：2012
• 出版时间：October 2012
• 年：2012
• 卷：33
• 期：10
• 页码：1239-1252
• 全文大小：353.5 KB
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• 作者单位：1. Department of Applied Mathematics, Indian School of Mines, Dhanbad, 826004 Jharkhand, India
• ISSN：1573-2754

文摘

The present work deals with the possibility of propagation of torsional surface wave in an inhomogeneous crustal layer over an inhomogeneous half space. The layer has inhomogeneity which varies linearly with depth whereas the inhomogeneous half space exhibits inhomogeneity of three types, namely, exponential, quadratic, and hyperbolic discussed separately. The dispersion equation is deduced for each case in a closed form. For a layer over a homogeneous half space, the dispersion equation agrees with the equation of the classical case. It is observed that the inhomogeneity factor due to linear variation in density in the inhomogeneous crustal layer decreases as the phase velocity increases, while the inhomogeneity factor in rigidity has the reverse effect on the phase velocity.