Network Identification Performance: (1) Simulations for the Middle East/NorthAfrica, and (2) Maximum Likelihood Estimates of Teleseismic mb for the GSETT-3 Primary Network

摘要

We have simulated the detection and identification performance of the current andproposed IMS seismic networks in the Middle East/North Africa. The identification performance of a network is strongly dependent upon regional source and propagation variability. However, knowledge of those variations allow one to estimate their effects and to know that in some areas certain discriminants can work and in other areas they do not. Data sources included published results on wave propagation in this region and incorporated analyses of data taken by Vernon, et al, (1996) in Saudi Arabia. The maximum likelihood estimates of magnitude (Ringdal, 1976) was developed to improve measures of signal amplitudes which are below detection levels in some or all of the network as pointed out by Von Seggern and Rivers (1978), values of m sub b derived from arithmetic mean tend to have a positive bias, which may be eliminated by the use of maximum likelihood estimates. In this report, we simulate a suite of earthquakes recorded at the GSETT-3 Alpha network, and compare the mb is computed using the two methods with true values.