PROBABILISTIC MACROSEISMIC HAZARD ASSESSMENT FOR NICARAGUA (PRELIMINARY-RESULTS)

A probabilistic macroseismic hazard assessment has been done for Nicar agua. For this, the most complete catalogue for Central America, compi led by NORSAR in Norway has been used. In this catalogue, empirical in tensity attenuation relations were found. Using these empirical relati ons, magnitudes were changed to epicentral intensities expected in sit es where no intensities had been reported. The calculated intensities from a polygon surrounding Nicaragua were used to assess the macroseis mic hazard in the region. For the whole polygon, the cumulative intens ity frequency was calculated resulting in a b-value of 0.60 for an int ensity interval of V-IX. The time completeness was also studied indica ting that, for strong events causing higher intensities (I-0 greater t han or equal to VII), the catalogue is complete for events that have b een recorded since 1840. The whole polygon was cut into independent se ismotectonic regions where the statistical procedure (intensity freque ncy and time completeness) was done.