Crustal dynamics study of the unstable North Egyptian shelf through satellite gravity data and inverse/forward modeling

Abstract

The crustal architecture of northern Egypt, characterized by its tectonic complexity, remains poorly understood due to insufficient seismic data, limited coverage, and inaccuracies in prior gravity models. Recent advancements in satellite gravity methods, however, provide new opportunities to resolve crustal thickness variations with greater precision. In this study, we integrate GOCE gravity data, topography, sediment distributions, and seismic receiver functions to construct a high-resolution Moho depth model for the region. Using inverse and forward modeling techniques, we invert Bouguer anomalies from the GOCO06 gravity field and incorporate data from 50 seismic stations to constrain the model. Our results reveal significant variations in Moho depth, ranging from 23 to 38 km, with thinning to 23–29 km along the coastal zone and thickening to 35–38 km eastward toward the Sinai Peninsula and Red Sea. Forward modeling of three 2.5D crustal cross-sections further elucidates key tectonic features, including [specific features, e.g., fault zones, crustal thinning], which provide new constraints on the region’s tectonic evolution. This integrated approach, combining gravity modeling with seismic and geological constraints, offers a robust crustal thickness model that advances our understanding of northern Egypt’s tectonic history and structure. The findings have important implications for seismic hazard assessment and provide a foundation for future seismic data collection in the region.