PROPAGATION OF TORSIONAL SURFACE-WAVES IN DRY SANDY MEDIUM UNDER GRAVITY

This paper studies the possibility of propagation of torsional surface waves in a gravitating earth with a dry sandy medium. The mathematica l analysis of the problem has been dealt with in the Whittaker functio n. Assuming the expansion of the Whittaker function to linear terms, i t is concluded that the gravity field will always allow torsional wave s to propagate. The expansion of the Whittaker function to quadratic t erms shows that two such wave fronts may exist. Finally, it is conclud ed that the sandy medium without support of a gravity field cannot all ow the propagation of torsional surface waves, whereas the presence of a gravity field always supports the propagation of torsional surface waves regardless of whether the medium is elastic or dry sandy.