Contour mapping of seismic areas by numerical filtering and geological implications

Abstract

A method is described that makes possible the identification
of the independent seismic units of a given area (Caputo and Postpischl,
1973 b).
The seismic information is treated as a bidimensional signal disturbed
by a certain background noise. The filtering of this noise makes it possible
to delineate the seismic areas objectively.
An indirect check on the method was made by estimating with respect
to the various regions identified the a and /J parameters of the law
Ny = a e~Py
which gives the number of earthquakes with magnitude (intensity) greater
than or equal to y.