Investigations of Tectonic Stress

The estimation of the non-hydrostatic stress field of the earth can be achieved through the use of existing mb - Ms data for earthquakes. In this report the basis for this approach is discussed in terms of prediction of mb and Ms from theoretical relaxation source models for earthquakes inbedded in contemporary earth models. Comparisons of these predictions with observed data indicates that is the observed mb - Ms data is grouped with respect to source type and spatial tectonic aone, that basic source parameters and tectonic characteristics of the zone, particularly stress field characteristics, can be obtained. In addition, a basis of understanding of mb - Ms variations for earthquakes is established and this then provides a basis for predicting and understanding mb - Ms type discriminants for explosions and earthquakes. Personally Identifiable Information (PII) was redacted.