Abstract

A sequence of major seismic events reaching Ms 7.3, with thrust faulting mechanisms, occurred from 1891 to 2003 in the central Tell Atlas of Algeria located along the Africa–Eurasia plate boundary. Previous neotectonic investigations show that earthquake faults of the central Tell Atlas have the potential to generate large magnitude earthquakes. We calculate the level of stress change that promotes the occurrence of a seismic sequence, taking into account the earthquake fault parameters, their uncertainties, the eastward earthquake migration, the seismicity rate change, and the interseismic strain accumulation. The computed coulomb failure function (ΔCFF) includes the seismicity rate and the stress transfer with fault interaction. The ΔCFF modeling shows 0.1–0.8 bar increase on fault planes at 7 km depth with a friction coefficient μ=0.4 with stress loading lobes on targeted coseismic fault zone and location of stress shadow across other thrust‐and‐fold structures of the central Tell Atlas. The coulomb modeling suggests a distinction in earthquake triggering between moderate‐sized zones and large earthquake rupture zones. Following the 2003 earthquake, Global Positioning System, Interferometric Synthetic Aperture Radar, leveling studies, and aftershocks show that postseismic cumulative moment release amounts to 17.08%, which suggests an additional static stress change. In addition, the presence of fluid and related poroelastic deformation is considered as another parameter that favors stress increase and fault interaction. Modeling the stress change and fault interaction near major cities may contribute to a better constraint of the seismic‐hazard assessment and risk mitigation in northern Algeria.

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