A quantitative evaluation of teleseismic explosion records

Abstract

The examination of array records from underground nuclear explosions has produced the qualitative picture of the generation of simple signals which are transmitted to teleseismic distances along paths which exert comparatively little effect. At the recording sites, complications in the recorded signal are caused by crustal inhomogeneities local to the site. By using records from exceptionally good sites, or those where processing techniques eliminate the complications in the records, the combined effects of source signal and transmission path can be studied. To a first approximation, explosion source functions have been quantitatively defined and therefore quantitative data about the transmission path can be deduced. Specifically, data on the non-elastic properties of the mantle have been obtained. With the source and transmission paths defined, the character of the record complication at the poorer sites can be examined with the hope of producing deconvolution operators largely to eliminate the effects of crustal inhomogeneities. Conversely where the recording site characteristics are known, then records from earthquakes at teleseismic distances can be examined with a view to determining the source function. Preliminary work on the quantitative evaluation of earthquake source functions will be described.