next up previous
Next: The problem Up: Draft On the relationship Previous: Draft On the relationship




A nonzero isotropic moment of a seismic source does not by itself indicate a change of volume, nor does its absence indicate a constant volume. Any isotropic moment may be associated with any positive or negative volume change. A relationship between the isotropic moment and the volume change can only be established when the geometric boundary of the source is precisely defined. A definite and general relationship exists however between the isotropic moment and the volume displaced through any spherical surface enclosing the source.

Erhard Wielandt