Focal zone model and seismic event location based on amplitudes pP phases

This article is written as a continuation of the previous issues by the theme “Focal zone model”. Work carried out in a frame of investigation directed to elaboration of automated determination of the core events depth. As a base tool, a modified algorithm of location was used, supplemented with the simplex method of minimization. Early studies showed that the method built on the basis of an over determined mathematical task solution, that determined a point, doesn’t take into account the main aspect – the effect bias to the environment determined by volume and distribution of movements inside the focal zone. Criteria of received solution is minimum of Root Mean Square residuals (RMS). In solution of the formulated task depth phases pP were used. The detailed investigation showed that it is possible to consider that radiation from source of P waves is a continuation on initial stage of a source activity. The same can be said for pP phases registration. This give us the ability to construct an algorithm using the maximum of the seismic energy radiation as a criterion of the final solutions.