An Updated Earthquake Catalogue and Source Model for Seismic Hazard Analysis of Pakistan

Abstract

In this study, an updated earthquake catalogue and seismic source model for Pakistan region (bounded by latitude 20°–40° N and longitude 58°–83° E) are developed. The updated catalogue consists of published historical (10 to 1900 CE) and instrumental earthquake events (1900 to 2018 CE) with moment magnitude (Mw) ≥ 4.0. For this purpose, several international and national databases were accessed for collecting the historical and instrumentally recorded earthquake events occurred in the study region. The collected data from various sources were homogenized in a single moment magnitude scale. Several empirical relations were developed for conversion of earthquake magnitude in other scales to moment magnitude. The datasets are homogenized, declustered, and processed to evaluate complete intervals for different magnitude ranges. Using the developed catalogue and considering the seismo-tectonic features of the region, a number of shallow and deep area source zones are delineated to develop an improved seismic source model for Pakistan. The source model for spatially smoothed background seismicity is also developed using the updated catalogue. The developed catalogue and seismic source models can be reliably used to conduct an updated probabilistic seismic hazard assessment of Pakistan.