-The Tell-Rif (Tell in Algeria and Tunisia; Rif in Morocco) is the orogenic system fringing to the south the West Mediterranean basins. This system comprises three major tectonic-palaeogeographic zones from north to south: (1) the internal zones (AlKaPeCa for Alboran, Kabylies, Peloritan, Calabria) originating from the former northern European margin of the Maghrebian Tethys, (2) the "Flyschs zone" regarded as the former cover of the oceanic domain and (3) the external zones, forming the former southern Maghrebian Tethys margin more or less inverted. The Tell-Rif is interpreted as the direct result of the progressive closure of the Maghrebian Tethys until the collision between AlKaPeCa and Africa and, subsequently, the propagation of the deformation within Africa. This gives a consistent explanation for the offshore Neogene geodynamics and most authors share this simple scenario. Nevertheless, the current geodynamic models do not completely integrate the Tell-Rif geology. Based on the analysis of surface and sub-surface data, we propose a reappraisal of its present-day geometry in terms of geodynamic evolution. We highlight its non-cylindrical nature resulting from both the Mesozoic inheritance and the conditions of the tectonic inversion. During the Early Jurassic, we emphasize the development of NE-SW basins preceding the establishment of an E-W transform corridor connecting the Central Atlantic Ocean with the Ligurian Tethys. The Maghrebian Tethys developed just after, as the result of the Late Jurassic-Early Cretaceous left-lateral spreading between Africa and Iberia. By the Late Cretaceous, the occurrence of several tectonic events is related to the progressive convergence convergence between the two continents. A major pre-Oligocene (pre-35 Ma) compressional event is recorded in the Tell-Rif system. The existence of HP-LT metamorphic rocks associated with fragments of mantle in the External Metamorphic Massifs of the Eastern Rif and Western Tell shows that, at that time, the western part of the North-African margin was involved in a subduction below a deep basin belonging to the Maghrebian Tethys. At the same time, the closure of the West Ligurian Tethys through east-verging subduction led to a shift of the subduction, which jumped to the other side of AlKaPeCa involving both East Ligurian and Maghrebian Tethys. Slab rollback led to the development of the Oligo-Miocene back-arc basins of the West-Mediterranean, reworking the previous West Ligurian Tethys suture. The docking of AlKaPeCa against Africa occurred during the Late Burdigalian (17 Ma). Subsequently, the slab tearing triggered westward and eastward lateral movements that are responsible for the formation of the Gibraltar and Tyrrhenian Arcs respectively. The exhumation of the External Metamorphic Massifs occurred through tectonic underplating during the westward translation of the Alboran Domain. It resulted in the formation of both foredeep and wedge-top basins younger and younger westward. The lack of these elements in the eastern part ...
The Rif belt (northern Morocco) is a mountain chain located at the junction between the Mediterranean and Central Atlantic Domains. Although the Rif belt underwent important Cenozoic (i.e., Alpine) shortening, remnants of the Mesozoic North African rifted margin are preserved in its external zones. This contribution aims to characterize the Mesozoic architecture and polyphase rifting history of this rifted margin. We present detailed field evidence and geochronological data from two palaeogeographic zones (Mesorif and Intrarif) preserving remnants of the former North African distal margin. The Mesorif conserves lithostratigraphic associations characterized by mafic intrusive rocks overlain by dismembered and discontinuous blocks of Lower Jurassic carbonates covered by Middle to Upper Jurassic sediments. U‐Pb zircon dating of four samples from this gabbroic complex shows ages close to the Triassic‐Jurassic boundary (195–200 Ma). The gabbros were emplaced within the continental crust at the end of the first Triassic rift event and exhumed shortly after during a second Middle Jurassic rift event, which presents exceptional rift‐related structures. The most distal part of the margin is exposed in the Intrarif. In this unit, the Beni‐Malek serpentinized peridotites exhibit ophicalcites with uppermost Jurassic limestones resting conformably on top, suggesting that exhumation of the mantle occurred at the distal part of the North African margin at this time. When integrated, these new evidences enable us to discuss the evolution of the western part of the North African rifted margin and its relations with the Moroccan Atlantic margin and Tethys system.
This reply provides us the opportunity to further explain and discuss the differences between the successive models proposed by Michard et al. (2014Michard et al. ( , 2018Michard et al. ( , 2020 and ours. Their comment focuses on three main points regarding (1) the general structure and paleogeographic meaning of the Senhadja Nappe, (2) the geochemical characteristics and petrography of the MGC, and finally (3) the interpretation of geochronological data. Detailed answers to the major points discussed in the comment are provided and discussed below.Eventually, in the light of our observations and results, we will show that the alternative model tentatively proposed by Michard et al. (2020) should be simply abandoned. Lithostratigraphy and Structure of the Senhadja NappeThe structure of the Senhadja Nappe was extensively described in Gimeno-Vives et al. (2019), recognizing, after the pioneer work of Favre et al. (1991), the remnants of the North African rifted margin. We recall here our main observations but also provide additional and original data, such as field pictures and thin section descriptions, confirming our initial results.The Senhadja Nappe is characterized by a complex lithostratigraphic association with significant lateral variations (Figures 1 and 2). An idealized lithostratigraphy from bottom to top consists of the MGC overlaid by Upper Triassic evaporites, Lower Jurassic carbonate platform, and Middle Jurassic to Lower Cretaceous detrital sequences (Favre, 1992;Gimeno-Vives et al., 2019;Papillon, 1989).The contact between the overlying Mesozoic cover and the underlying MGC is of critical importance and is described in Gimeno-Vives et al. (2019). In that respect, the following statement by Michard et al. (2020)
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