Multichannel Deconvolution of P Waves at Seismic Arrays
Abstract
The results of a new multichannel deconvolution method applied to array recordings of teleseismic P waves are presented and interpreted in terms of possible surface reflections and other arrivals from Nevada Test Site, Eastern Kazakh Test Site, and Astrakhan nuclear explosions. The deconvolution method uses the well-known fact that P wave spectra can be decomposed into source and receiver spectral factors. Results are discussed in terms of the outcomes of other, less complex deconvolution methods including spectral ratio techniques for estimating pP delay times and stacked deconvolution methods for enhancing the pP phase on seismic records. For most events, the deconvolved source time functions appear to contain a pP arrival but they also show later, unexplained arrivals. The site functions are also complex in many cases. About half of the late coda in P appears to be due to each of the source and the receiver. Recordings for an Eastern Kazakh cratering event show a distinctly different source function when compared to deeper, buried explosions at the same test site. From the deconvolved source-time functions, the cratering to non- cratering m sub b bias is estimated to be between 0.09 and 0.22 magnitude units. Keywords: Primary waves (Seismic waves); Seismic data; Maximum likelihood estimation; Nuclear explosion detection.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 20, 1986
- Accession Number
- ADA174947
Entities
People
- A. C. Lees
- E. Smart
- R. H. Shumway
- Z. A. Der