Accession Number : ADA258041


Title :   Simultaneous Inversion of Explosion Size and Path Attenuation Parameters with Crustal Phase


Descriptive Note : Semi-annual rept. no. 2, 5 Apr-23 Oct 1992


Corporate Author : TELEDYNE GEOTECH ALEXANDRIA VA ALEXANDRIA LABS


Personal Author(s) : Jih, Rong-Song


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a258041.pdf


Report Date : Oct 1992


Pagination or Media Count : 41


Abstract : An iterative procedure is presented to invert for the path gamma and the event mb(Lg) values simultaneously without using any a priori information about the path gamma. This joint inversion scheme can be applied to data from multiple test sites as well. With this iterative method, it is rather easy to incorporate the appropriate boundary condition into the inversion. The iterative scheme is less sensitive to rounding errors, and hence it is numerically more accurate than those direct methods based on matrix factorization or Gaussian elimination. When the number of equations becomes large, the iterative method is often the only practical means to tackle the problem. The iterative joint inversion scheme has been applied to Nuttli's Semipalatinsk Mb(Lg) data set furnished by DARPA/NMRO. The result indicates that the majority of Qo values Nuttli used in his pioneering Lg study appear to be very good except for the path from Eastern Kazakh to COP (Copenhagen, Denmark). An 8% increase in Nuttli's postulated coefficient of anelastic attenuation, Qo, for this particular path is necessary. Overall, Nuffli's (1986b, 1987) mb(Lg) data set for Semipalatinsk explosions appears to have very good quality with a standard deviation (of single observation) of only 0.1 magnitude unit.


Descriptors :   *PARAMETERS , *PATHS , *EXPLOSIONS , *ATTENUATION , *PHASE , *INVERSION , TEST AND EVALUATION , NUCLEAR EXPLOSIONS , BOUNDARIES , COEFFICIENTS , STANDARDS , HOISTS , DENMARK , STANDARD DEVIATION , ELIMINATION , ITERATIONS , NUMBERS , EQUATIONS , AMPLIFICATION , VALUE , MAJORITIES , ERRORS , QUALITY , UNDERGROUND EXPLOSIONS , OBSERVATION , SITES , STATIONS , MODELS


Subject Categories : Numerical Mathematics
      Nuclear Explosions and Devices(non-military)
      Nuclear Weapons


Distribution Statement : APPROVED FOR PUBLIC RELEASE