Evaluation of the reliability of a seismic network: the HSSN (Israel) as an example

Under the assumption that an earthquake can be analyzed if it is detected and recorded by at least four stations, various scenarios leading to the total loss of ability to acquire sufficient data for seismological analysis are described. These scenarios are presented by constructed fault-trees, to each branch of which is assigned the empirical annual probability of occurrence (equipment malfunction or external disturbance). This approach has been applied to a seven station local network (HSS) which operates in parallel with the Israel national seismic network. In this example it is estimated that there is an annual probability of 3.10^-4 that an earthquake of magnitude 3.0 or higher would not be detected and analyzed. -from Authors