New seismic hazard assessment for Nicaragua.

Abstract

An estimation of seismic hazard of Nicaragua is presented. It started from new earthquake catalogue preparation and response acceleration spectra (RSA) determination from accelerograms registered by Nicaraguan stations. It was applied the Esteva-Cornell probabilistic approach by using R-CRISIS program. Seismicity was analized in 43 source zones by adjusting a modified Gutenberg-Richter model. Zones outside Nicaragua (another 37 as published by other authors) have little influence in the Nicaraguan territory. The RSA were used for determining the GMPE closest to recorded values. They were normalised to a common value of VS30 and a correction determined by residual analysis was applied to each one. They were selected 5 corrected GMPE. 24 variants of seismicity-GMPE combinations were processed by logic tree techniques in a grid of 0.1°×0.1°. The results (occurrence frequency of events with different RSA) were processed with sample statistics and percentil 84 was selected for making maps for different return periods (Tret). A deaggregation analysis was done for the city of Managua.