Accession Number : ADA320858

Title :   A Complete Model for Seismic Source Behavior of Peaceful Nuclear Explosions.

Descriptive Note : Final rept. 21 Apr 93-31 Mar 94,

Corporate Author : CALIFORNIA UNIV SAN DIEGO LA JOLLA INST OF GEOPHYSICS AND PLANETARY PHYSICS

Personal Author(s) : Burdick, Lawrence

PDF Url : ADA320858

Report Date : 20 NOV 1995

Pagination or Media Count : 30

Abstract : The four most widely accepted forms used to represent the source time history of a nuclear explosion have been unified into a single simple time domain expression. A unique feature of this expression is that the Mueller-Murphy representation is given in terms of two characteristic frequency parameters (k's) and two independent source shaping parameters (B's). The Haskell, Helmberger-Hadley and von Seggern-Blandford representations have always been specified by one of each. There are a total of ten free parameters in the generalized fitting function which are too many for fitting any one type of seismic observation. Yet, they may be useful for unifying different types of data. In particular the Mueller-Murphy parameters are useful for modeling cavity scaling observations and the Helmberger-Hadley are best for studies of near field seismograms. However, there is a clear need to relate the investigations of both types of information. No unique mathematical relationship between the ten free parameters exists, but the differences between the pulses they predict can be measured in a least squares sense. To accomplish this, we have assumed that the Mueller-Murphy source is in fact correct and have found those source functions of the other three representations which approximate it most closely. An important result is that each of the four realizations of the unified source representation can be related to the others in a meaningful way, and the differences are negligible in a least squares sense. Future work needs to be directed at unifying the scaling laws of each representation which is where the real physics lies.

Descriptors :   *NUCLEAR EXPLOSIONS, *YIELD(NUCLEAR EXPLOSIONS), *UNDERGROUND EXPLOSIONS, *SEISMIC DATA, NUCLEAR EXPLOSION TESTING, LEAST SQUARES METHOD, SEISMIC WAVES, EARTHQUAKES, FITTING FUNCTIONS(MATHEMATICS).

Subject Categories : Seismology
      Nuclear Explosions and Devices(non-military)

Distribution Statement : APPROVED FOR PUBLIC RELEASE