LARGE APERTURE SEISMIC ARRAYS
Abstract
Four topics are discussed in this report. The first topic is the detection of underground nuclear explosions in the presence of large natural events. Previous studies of this problem have been extended and partially confirmed by applying calculations to additional data and by considering the effect of strengthening certain assumptions. The use of a LASA for estimating epicenters by beamforming and other methods is the second topic considered in this report. Recent studies of this topic have employed computer-aided simulations with controlled amounts of additive noise and travel-time anomalies to examine the relative performance of different algorithms for epicenter estimation. The third topic considered in this report is an analysis of detection and false alarm probabilities for a DIMUS array. Taking advantage of a strong analogy between this problem and a standard problem in coding theory, bounds and asymptotic expressions for these probabilities are described, and the signal-to-noise ratio loss of the DIMUS array over the corresponding analog array is analyzed as a function of several parameters. Finally, the previously developed automatic pP test has been re-examined with a view toward evaluating its performance and simplifying its implementation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1968
- Accession Number
- AD0667794