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Abstract: The Red Sea is part of a long system of rifts, which formed as a result of African–Arabian continental breakup during the Oligocene–Miocene. Two phases of volcanism are generally accepted, the first occurring 31mya and the second ∼25mya. Sometime between 20 and 14Ma motion along the Dead Sea fault developed and new plate geometry arose to reflect the collision of Arabia with Eurasia. As a result, extension along the northern Red Sea switched from rift-normal (N60°E) to highly oblique and parallel to the newly formed fault. Sea-floor spreading commenced in the southern Red Sea at about 5Ma leading to a change in the way extension is accommodated along its length. In general the Red Sea is divided into three segments with distinct morphologies and geophysical characteristics: southern (between 15°N and 20°N) – active seafloor spreading, central transition zone (20–23.3°N) with discontinuous axial trough and isolated cells of seafloor spreading, northern dominated by an axial depression is currently in the late stages of continental rifting. Magnetic and gravity data support the differences between the southern and northern sections, while new tomographic studies indicate that the central section behaves as a separate entity that does not act as a transfer zone that gradually transmits processes from south to north. Rifting in the southern Red Sea is under the influence of the Afar plume, while in the north, new evidence points to a strong connection with the Dead Sea fault (fault-parallel and perpendicular features indicating motion parallel to the fault). Motion along the fault may be the stronger force acting on the northern Red Sea and hence, it will behave differently than the southern section. The northern section may act as an area, which transfers motion from seafloor spreading (central-southern Red Sea) to strike-slip (Dead Sea fault). [Copyright &y& Elsevier]

Abstract: The Galilee study area, northern Israel, is at present an uplifted, steep continental margin that formed mainly during the Jurassic and has a large positive isostatic anomaly. Since the Jurassic, it was modified by several tectonomagmatic events, which this study attempts to define and classify by updating, reprocessing and reinterpreting gravity, aeromagnetic and geological data. The prominent Rehovot-Carmel N–S positive reduced-to-pole (RTP) magnetic anomaly caused by the Gevim Volcanics, as well as the coexisting Helez-Gaash high Bouguer gravity and the Pleshet low Bouguer gravity, represent the deep (>5km) Permo-Triassic dominant horst and graben structure of Israel. The Jonah Ridge and Beirut high SW–NE RTP magnetic anomalies in the Levant basin delineate the Levant continental edge that is marked by a deeply buried horst covered by a Late Cretaceous volcanic complex. The Asher and Devora Jurassic volcanics appear to be responcible for the Atlit and Galilee negative magnetic anomalies and for significant negative gravity anomalies which became clear after removing gravity effect of the upper (post-Turonian) light density sediments from the observed gravity. The volcanics extend along a SW–NE belt parallel to the strike of the Moho. It is suggested here that the Carmel-Gilboa fault propagated during the Late Cretaceous from the Levant basin across the Galilee area southeastward to form the Azraq-Sirhan graben in Jordan. As such, it forms a right-step, en echelon, dextral strike-slip fault with associated tectonic basins of various shapes. During the Oligocene and before formation of the Dead Sea transform (DST), the reactivation of the Azraq-Sirhan graben was accompanied by tectonic driven rift propagation in the opposite direction, from Azraq-Sirhan to northwest. It dispersed into many faults and terminated ∼10km west of the present DST. During the Miocene it propagated in the same direction and includes internal volcanic activity. The numerous Miocene-Pliocene volcanic centers on the margins of the DST indicate that the preferred pathway for magmas at that time was not within the deep basins of the DST. [Copyright &y& Elsevier]