## 2 Seismotectonic Framework  
The Red Sea embodies a significant segment of an expansive rift system that spans multiple geologic features. This region serves as a potential model for understanding the initial rupture of continental lithosphere and its subsequent transformation into oceanic spreading centers, which are key elements in plate tectonics [6]. Recent studies have elucidated the absolute and relative timing of key events in the Red Sea's geological history, categorizing them into six major phases. The first stage is marked by plume-related basaltic trap volcanism, originating around 31 Ma in Ethiopia, NE Sudan, and SW Yemen, followed by rhyoliticity activity near 30 Ma [21]. This early magmatism occurred without any demonstrable extension. The second phase involved marine syntectonic sediment deposition on the continental crust in the central Gulf of Aden between 29.9 and 28.7 Ma, signifying early Oligocene rifting east of Afar [6]. The third phase saw the formation of a small rift basin in the Eritrean Red Sea around 27.5-23.8 Ma, coinciding with extension and rifting within Afar and the creation of the Red Sea as a rift basin. A renewed phase of volcanism characterized the fourth stage, which began around 24-23 Ma. This activity comprised basaltic dikes as well as layered gabbro and granophyte bodies, and extended from Afar and Yemen to northern Egypt. This phase was accompanied by substantial rift-normal extension and deposition of mostly marine and marginal marine syntectonic sediments [4; 5]. Regions such as the Gulf of Aqaba and the Dead Sea Rift exhibit elevated and concentrated seismic activity. These areas are tectonically active, linked to the opening of the Northern Red Sea and the Gulf of Aqaba, and also to a major continental strike-slip plate boundary [21; 22; 23]. The Gulf of Aqaba has experienced left-lateral strike-slip faulting with a 110 km offset from the early Tertiary period to the present. The Arabian Plate boundary extends from the Afar region through the Gulf of Aden, eventually connecting to the Zagros fold belt (see Figure 1a). The Red Sea region exhibits seismic activity at varying levels in its northern, southern, and central areas, closely linked to its tectonic characteristics. The Gulf of Aqaba and Suez, with their strike-slip faults, are active, and the Red Sea's axial trough is characterized by concentration of seismic activity, especially at intersections with northeast-trending strike-slip faults [5]. Fault plane solutions from major earthquakes indicate that the region acts as a divergent boundary between the Arabian and Nubian Plates, marked by seafloor spreading northwestward. Seismic activity is predominantly shallow, with over 97% of seismic events in the two Gulfs occurring at depths of less than 10 km. In contrast, seismicity in the Northern and Southern Red Sea varies in depth, suggesting lithospheric deformations in both the upper crust and the uppermost mantle [26; 27]. The seismicity in the Red Sea is closely related to the tectonic activities at the spreading center and along the transform faults segmenting the rift. These tectonic forces result in a complex pattern of seismic events, providing a unique opportunity to study the dynamics of plate tectonics, particularly in the context of nascent ocean basin formation. The seismic activity in the Red Sea is dominated by the complex interplay of tectonic movements due to the rifting and spreading processes. This active tectonic environment generates a spectrum of seismic events, from small tremors to moderate earthquakes. Figure 1: **(a)** Principal geological and tectonic characteristics of the Red Sea region, including the extensional ridges and oceanic troughs, as well as the adjacent elevated peripheries of the Arabian and Nubian Shield, accompanied by the dispersion of Late Cenozoic volcanic terrains, commonly known as narrats (adapted from [24]). **(b)** Spatial distribution of documented historical and instrumentally recorded seismic occurrences within the vicinity of the Red Sea (adapted from [25]).