DYNAMIC PROPERTIES OF JOINTED BODIES

Abstract

Various phenomena accompanying the passage of seismic signals through real media can be explained by the theory of the block structure and jointing of the medium. This theory explains the fact that the range of frequencies detected in earthquake foreshocks is much broader than would be expected in the case of a continuous medium. It also explains the finding of microseisms in zones of the crust accessible to measurement, both at the surface and in the interior. The existence of a combination of blocks whose sizes exhibit definite proportional relationships with each other is the most unexpected and original part of the theory. It is of interest to apply this theory of jointing to practical problems of geophysics, particularly those that are amenable to a variety of types of measurement. But owing to the complexity of the problem, the mathematical techniques investigating it has not been well developed. In the present paper, we propose a method of solving certain problems concerning jointed bodies. It is used to derive new results on the dynamic failure of joints.