Abstract: Layer-bound normal faults commonly form polygonal faults with fine-grained sediments early in their burial history. When subject to anisotropic stress conditions, these faults will be preferentially oriented. In this study we investigate how faults grow, evolve and interact within regional-scale layer-bound fault systems characterized by parallel faults. The intention is to understand the geometry and growth of faults by applying qualitative and quantitative fault analysis techniques to a 3D seismic reflection dataset from the Levant Basin, an area containing a unique layer-bound normal fault array. This analysis indicates that the faults were affected by mechanical stratigraphy, causing preferential nucleation sites of fault segments, which were later linked. Our interpretation suggests that growth of layer-bound faults at a basin scale generally follows the isolated model, accumulating length proportional to displacement and, when subject to an anisotropic regional stress field, resembling to a great extent classical tectonic normal faults.

Abstract: In this paper, we document the early stage of fault-zone development based on detailed observations of mesocale faults in layered rocks. The vertical propagation of the studied faults is stopped by layer-parallel faults contained in a weak layer. This restriction involves a flat-topped throw profile along the fault plane and modifications of the fault structures near the restricted tips, with geometries ranging from planar structures to fault zones characterized by abundant parallel fault segments. The ‘far-field’ displacement (i.e. the sum of the displacement accumulated by all the fault segments and the folding) measured along the restricted faults exhibiting this segmentation may have flat-topped shapes or triangular shapes when fault-related folding is observed above the layer-parallel faults. We develop a model from the observations. In this model, during the course of restriction, a fault forms as a simple isolated planar structure, then parallel fault segments successively initiate to accommodate the increasing displacement. We assume that, eventually, the fault propagates beyond the layer-parallel fault. This model implies first that fault widening is controlled by the fault capacity to propagate vertically in the layered section. Likewise, owing to restriction, fault growth occurs with non-linear increases in maximum displacement, length and thickness.

Abstract: The total offset across a fault zone may include offsets by discontinuous faulting as well as continuous deformation, including fault-related folding. This study investigates the relationships between these two components during fault growth. We established conceptual models for the distributions of displacement due to faulting (i.e. brittle component or near-field displacement), to folding (i.e. ductile component) and to the sum of both (i.e. far-field displacement) for different mechanisms of fault-related folding. We then compared these theoretical displacement profiles with those measured along mesoscale normal faults cutting carbonate-rich sequences in the Southeast Mesozoic sedimentary basin of France. The near-field and far-field displacement profiles follow either a flat-topped or a triangular shape. Several fold mechanisms were recognized, sometimes occurring together along the same fault and represent either fault-propagation folds, shear folds or coherent drag folds. In the last case, local deficit in the fault slip is balanced by folding so that the brittle and ductile components compose together a coherent fault zone. Common characteristics of these faults are a high folding component that can reach up to 75% of the total fault throw, a high displacement gradient (up to 0.5) and a strong fault sinuosity.

Abstract This volume combines original data in various fields from the offshore Levant Basin and adjacent continental slopes and platforms. The first group of papers document the tectonic structures and sedimentological patterns associated with the development of the Levant Basin. They identify the successive rifting events from the Late Palaeozoic to the Early Cretaceous, followed by a moderate tectonic activity. The contribution of external factors like global sea-level and climate changes to the sedimentation processes during the Mid-Cretaceous is discussed in the second set of papers. The final group presents new kinematics and age constraints on the Late Cretaceous to Neogene tectonic phases and discusses the relationship of the structures with the closure of the Neo-Tethys and separation of the Arabia plate. This collection of research papers demonstrates new concepts on the opening and crustal thinning of the Levant Basin and gives updated interpretations of the latter tectonic structures of the Levant.

Abstract The Levant area comprises the offshore Levant Basin (LB) (eastern corner of the Eastern Mediterranean) as well as the adjacent continental slopes and platforms of the African and Arabian plates. This area experienced major events of the geodynamical evolution of the Middle East, such as the Late Palaeozoic–Early Mesozoic Pangea break up, the Late Cretaceous–Cenozoic closure of the Neo-Tethys and individualization of the Arabian plate, as well as a set of external factors like global sea-level and climate changes. This volume combines original data from the offshore and onshore Levant in various fields, including sedimentology, palaeontology, sequence stratigraphy, geochemistry, structural geology, stress reconstitution and geophysics (seismic lines, palaeomagnetism). All together, these multidisciplinary approaches allow the review of the development of the LB and gain a better insight on the later geological history and deformation processes of the Levant provinces.

Abstract At the time of the opening of the Tethys Ocean the northern edge of Gondwana was affected by several rifting events. In this study, we used data from deep exploration wells, seismic profiles, and seismic depth maps to reconstruct the pattern of Tethyan rifting in the Levant region and to investigate its effects on the evolution of the Levant crust. The results show a several hundred kilometre wide deformation zone, comprised of graben and horst structures that extend from the inner part of the Levant to the marine basin offshore Israel. The structures are dominated by sets of NE–SW and NNE–SSW oriented normal faults with vertical offsets in the range of 1–8 km. Rifting was associated with a NW–SE direction of extension, approximately perpendicular to the present-day Mediterranean coast. Faulting activity progressed over a period of 120 Ma and took place in three main pulses: Late Palaeozoic (Carboniferous to Permian); Middle to Late Triassic; and Early to Middle Jurassic. The last, and the most intense, tectonic phase post-dates the activity in other rifted margins of northern Gondwana. Rifting was associated with the modification and stretching of the Levant crust. Our results demonstrate an extension discrepancy between the brittle deformation in the upper crust and the amount of total crustal thinning. Seismic reflection data shows that the Levant Basin lacks the characteristics of typical rifted margins, either volcanic or non-volcanic. The evolution of the basin may be explained by depth-dependant stretching, associated with the upwelling of divergent mantle flow and removal of lower crustal layers by decoupling along deep detachment faults.

Abstract Detailed study of outcrop and subsurface data of North Sinai indicates the existence of a NE–SW oriented region with very large asymmetric folds lying between the Nile Delta hinge zone and the Sinai hinge belt. The steep southeastern flanks of these folds are often associated with high-angle reverse faults. These folds continue northeastward in the Naqb Desert toward the Dead Sea transform. The North Sinai folds represent inversion anticlines formed by inversion of Mesozoic (Jurassic and probably Cretaceous) extensional basins during Late Cretaceous to pre-Miocene times. Mesozoic extension is related to the divergence between Afro-Arabia and Eurasia and opening of the Neotethys whereas inversion is related to the convergent movement between these two plates. The acme of inversion was at Campanian time. The central Sinai hinge belt is a zone of ENE–WSW oriented, right-lateral strike–slip faults that separate the folded area to the north from the tectonically stable area of central and southern Sinai. It responded to the convergent movement between Afro-Arabia and Eurasia by dextral transpression on the faults. Later reactivation of the eastern edges of these faults by drag on the west side of the Dead Sea transform took place in post-Miocene to Recent times.

Abstract The offshore area of North Sinai represents the northern extension of the Syrian Arc inversion structures into the southeastern Mediterranean region. Integration of detailed seismic interpretation of key tectonic events in offshore North Sinai and recently acquired gravity and magnetic data reveal structural deformation represented by large buried inversion anticlines that have played an important role in the geological history and hydrocarbon potential of the area. This tectonic inversion took place in the Late Mesozoic and continued slightly during the Cenozoic, and formed NE-trending asymmetrical folds. Three different phases of deformation have been detected in offshore North Sinai: (1) A Jurassic–Early Cretaceous extensional phase, which formed NE trending normal faults bounding asymmetrical half-grabens, (2) Post-Santonian–Middle Miocene positive inversion of these faults and half-grabens and (3) Post–Middle Miocene subsidence. A set of tectonosequences related to the opening and the subsequent convergence of the Tethys was mapped. Each identified tectonosequence has its own unique drive mechanism, geometry, and location with respect to the plate boundary. Recognition of these elements allows illustration of the Tethyan basin evolution of offshore North Sinai through time as well as understanding the tectonic and stratigraphic framework and effective prediction of the petroleum system.

Abstract Regional multichannel seismic reflection (MCS) profiles across the Egyptian continental slope, offshore the Nile delta, were recorded during the MEDISIS survey (conducted in 2002 on board the R/V Nadir ). The results of this survey allow an interpretation of the overall structure and evolution of this passive continental margin. The MCS data were processed using an amplitude preserving pre-stack depth migration technique, which has the advantage of providing a quantitative, and geometrically correct, image of seismic horizons. Well-defined reflecting events allow the identification of three main seismic units. The upper unit (a 7 km thick) is interpreted as the post-rift sedimentary cover of the margin; it includes an undisturbed Middle Cretaceous to Upper Miocene sedimentary pile, covered by thick Messinian (latest Miocene) salt-rich layers and by Pliocene to Quaternary sediments, locally intensively deformed by gravity tectonics. The underlying intermediate acoustic unit (6 km thick on average) is interpreted as the Mesozoic syn-rift sedimentary cover of the margin; the end of the last rifting event is marked by a strong angular unconformity, tentatively of Aptian age. The lower unit may correspond to the thinned continental crust of Africa (12 km thick on average in the study area) and its pre-rift cover. Its base is identified by strong, discontinuous reflector packages about 23–25 km below sea floor, interpreted as indicative of the Moho.

Abstract The Upper Barremian–Albian Levant Platform was studied in North Sinai and Israel (Galilee and Golan Heights) by bio- and lithostratigraphy, facies analyses, and sequence stratigraphy. Integrating shallow-marine benthic foraminifera (mainly orbitolines), ammonite, and stable isotope data resulted in a detailed stratigraphic chart. Transects across the shallow shelf in both regions are based on facies analysis and form the basis for depositional models. In both transects five platform stages (PS I–V) were identified, which differ significantly in their stratigraphic architecture, mainly controlled by local tectonics, climate and second-order sea-level changes. In North Sinai, a transition from a shallow-shelf that is structured by sub-basins through a homoclinal ramp into a flat toped platform is recognized, while the sections in North Israel show a transition from a homoclinal ramp into a fringing platform. Local normal faults influenced the depositional architecture of the Upper Barremian–Lower Aptian strata in North Sinai and were attributed to syn-rift extensional tectonics. Four second-order sequence boundaries were identified, bounding Mid-Cretaceous Levant depositional sequences. These well-dated second-order sequence boundaries are MCL-1 (Late Barremian), MCL-2 (earliest Late Aptian), MCL-3 (Lower Albian), and MCL-4 (Late Albian). The sea-level history of the Levant Platform reflects the Late Aptian–Albian global long-term transgression, while the second-order sea-level changes show good correlation with those described from the Arabian plate.

Abstract This study deals with the sedimentary evolution, tectonic configuration and global imprints of a Cenomanian–Turonian carbonate system located in northern Israel, on the central part of the Levant margin of the north Arabian Plate. Detailed sampling of field sections, mesoscopic features, petrography and microfacies form the database for this study. Facies units are integrated into high- and low-order cycles that comprise a sequence stratigraphic model. Two palaeo-highs, separated by a subsiding trough, all striking east–NE, govern the pattern of carbonate deposition in northern Israel. An additional subsiding region extended northward into Lebanon. Eustatic and palaeoenvironmental imprints are represented by earliest Cenomanian subaerial exposure; Early Cenomanian maximum flooding and oxygenation of hypoxic sea-floor; Middle Cenomanian high-stand progradation followed by forced regression and mass transport; Middle Cenomanian subaerial exposure; Late Cenomanian eutrophication during sea-level rise; Late Cenomanian subaerial exposure; latest Cenomanian–Turonian eutrophication and gradual development of the OAE-2 (oceanic anoxic event). A Late Cenomanian eustatic rise was locally masked by uplift and subaerial exposure. We conclude that the tectono-sedimentary regime of northern Israel represents an east–NE branch-off of the depositional strike from the north–south striking Levant margin, and that the carbonate system of this region was strongly influenced by eustasy and palaeoceanographic trends of the Tethys.

Abstract Two Cenomanian–Turonian boundary (CTBE) sections (KB3 and GM3) of the Karak–Silla intra-platform basin of the Eastern Levant carbonate platform, Jordan, are correlated based on high-resolution calcimetry. KB3 contains black shales with over 7 wt% total organic carbon (TOC). GM3 was deposited at shallower water depth and reveals four conspicuous gypsum beds used for sea-level reconstruction. Spectral analysis of carbonate content and TOC reveals forcing, mainly by the 100 ka cycle of Earth's orbit eccentricity. Whole rock stable carbon isotope data show a conspicuous positive δ 13 C excursion representing the Oceanic Anoxic Event 2 (OAE2). The carbon isotope records of KB3 and GM3 correspond well with the cycles in the δ 13 C record of the global stratotype (GSSP) at Pueblo (USA). The GSSP orbital timescale, thus, can be applied to the Jordan record. Furthermore, all stable isotope events defined in the English chalk reference record are recognized in Jordan. Our orbital model for the Jordan sequence-stratigraphical framework reveals approximately 1.2 (+0.2) Ma duration of a third-order sequence, proposed to represent one cycle of the long obliquity (1.2 Ma). This long-term period is superimposed on three fourth-order fluctuations of 400 ka length (long eccentricity; fourth-order sea-level fluctuations), each of which comprises four carbonate cycles (100 ka eccentricity; fifth-order sea-level fluctuations). Demise of the Levant platform occurred during the phase of decreasing δ 13 C values after OAE2 in the interval between the Cenomanian–Turonian (C–T) boundary and the end of the Early Turonian.

Abstract Study of a Cenomanian–Turonian sequence, including the oceanic anoxic event 2 (OAE2) in Central Jordan, yielded 22 ostracod species from the Middle–Late Cenomanian interval; no ostracods were found in the Early Turonian. The majority of the taxa have a wide geographical distribution along the southern shores of the Tethys; from Morocco in the west to the Arabian Gulf region in the east. Biogeographical homogeneity of the ostracod associations in North Africa and the Middle East reflects facilitated communication along the whole expanse of the southern Tethys margin during the Cenomanian, and suggests similar living conditions and absence of important geographical barriers that could hinder marine faunal exchange. Biostratigraphically, the investigated fauna revealed five informal ostracod biozones (I to V from older to younger). The recorded assemblages are characterized by ostracod faunas of typical marine shelf setting in biozone I, shelf lagoonal setting with fresh-water influence in biozone II, marine shelf setting with intervals of fresh-water supply in biozones III and IV, and reduced oxygen levels in the interval of biozone V. This sequence of biozones provides palaeontological evidence for the occurrence of an interval of enhanced fresh-water influence in Levant platform lagoons preceeding OAE2. A combined biostratigraphic and chemostratigraphic time scale based on stable carbon isotopes reveals the first appearance of Reticulicosta kenaanensis , previously described as an Early Turonian indicator species already in the Late Cenomanian. Absence of ostracods throughout the Early Turonian indicates environmental conditions adverse to ostracods during most of OAE2 and its aftermath interpreted to reflect strong water column stratification.

Abstract Orientations of folds and small faults were measured in Turonian and Senonian rocks along the western limb of the Ramallah monocline in Israel, one of the structures comprising the Syrian Arc fold belt (SAFB). The minority of the folds, aligned NNE–SSW, are compatible with the WNW–ESE shortening trend of the SAFB, whereas the majority of them, aligned ENE–WSW, are not compatible with this shortening trend. Kinematic analysis of faults’ attitude indicates NNW–SSE shortening and ENE–WSW extension in accordance with the shortening of the majority of folds. Based on the folds trends, scale, and geometry, as well as the associated fault kinematics, we conclude that the folding mechanism is tectonic shortening and not intraformational folding due to landsliding or collapse owing to karst activity as previously postulated. We propose that a minority of the folds, compatible with the major trend of the Ramallah monocline, are parasitic small folds within the SAFB. The majority of the folds, which are not compatible with the SAFB, were formed owing to NNW–SSE shortening that has been associated with Miocene to Recent movement along the Dead Sea Transform.

Abstract The Arabian, African and Eurasian plates interact in the Levantine region. Despite numerous studies of the region, many geological issues relating to Mesozoic times remain unresolved. The Lebanon passive margin is a key area for understanding Neo-Tethyan sedimentary history during this period. The Jurassic succession in Lebanon is well exposed and thick (more than 1000 m). It is more or less complete and relatively undeformed. With a few recent exceptions most studies of the area were made in the 1950s and so the sedimentary evolution of the Jurassic is only partly understood. This study provides (1) a new sedimentary and sequence stratigraphic framework, and (2) a new biostratigraphic framework based on benthic foraminifera and calcareous algae. Palaeoenvironmental and geodynamic conclusions are inferred. Jurassic outcrops occur in both the Mount Lebanon and the Anti-Lebanon areas. Here, they were studied essentially in Mount Lebanon. The Jurassic succession can be divided into three parts: (1) the lower part (Kesrouane Formation) is a thick succession of marine limestones or dolomites; (2) the middle part (Bhannes Formation) consists mainly of basaltic eruptive rocks associated with pyroclastic strata; (3) the upper part (Bikfaya Formation) is a succession of marine limestones. During the Bathonian, Callovian, Oxfordian and parts of the Kimmeridgian, a large epicontinental shelf, with very shallow marine environments, extended across Lebanon (Kesrouane Formation). The period was characterized by a stable platform morphology. It was a tectonically quiet period, although intense subsidence allowed the accumulation of a thick sediment package. During the Kimmeridgian, the carbonate platform regime that had dominated Lebanon during the Middle Jurassic came to an abrupt end, as evidenced by a regional unconformity, a regression and block faulting. This rifting phase is associated with a volcanic event (Bhannes Formation) that is recognized from northern to southern Lebanon. During the Lower Jurassic (Kimmeridgian p.p. to Tithonian p.p. ) shallow marine carbonate shelf deposits are observed again (Bikfaya Formation), indicating a marine transgression. This last formation exhibits rapid lateral thickness variations, because of active block faulting and erosion, and is overlain by continental sandstones of the basal Cretaceous.

Abstract The tectonic history of the central part of the Levant domain (Lebanon) is re-evaluated. Examination of the tectonic structures and mechanical analysis of the meso-scale brittle deformation indicate that Lebanon has experienced four major tectonic events since Late Mesozoic time. The first was an Early Cretaceous extensional phase orientated north–south to NNE–SSW. It produced WSW–ENE to WNW–ESE normal faults with offsets up to several hundreds of meters and led to the development of an approximately WNW–ESE-trending basin. A second extension, with similar driving stresses, occurred during Eocene time and persisted, perhaps until Oligocene times. The Early Neogene period marked a dramatic change in the structural evolution of Lebanon after which strike–slip and reverse faulting and folding dominated. During Early Miocene times, an east–west compression produced moderate folding and faulting. A second, but much more severe, folding event occurred during Late Miocene time owing to a NNW–SSE compression. This new tectonic history allows the discussion of several aspects of the Eastern Mediterranean basin development and the later deformation of its continental margin and surroundings, in particular: (1) the driving mechanisms of the Levant basin opening; (2) the inversion of its adjacent margin; and (3) the age, origin, and evolution of the restraining bend of the Dead Sea Transform in Lebanon.

Abstract A study carried out on widespread sites of the Aptian–Albian formations in Lebanon led to two palaeomagnetic directions corresponding to the primary magnetization ( N =37 sites, D=307.1°, I=23.7°, k=18 and α 95 =5.5° after tilt correction and to a post-folding remagnetization ( N =18 sites, D=346.3°, I=49.2°, k=108 and α 95 =3.2° before tilt correction). Comparison of these data with previous palaeomagnetic results for the Jurassic age in Lebanon and expected directions from African apparent polar wander path yields evidence of three different counter-clockwise regional rotations, of the order of 33° before Aptian deposition, of 11° during Late Miocene times, and of 18° since Miocene period. The two last rotations are related to the relative displacement of the African and Arabian plates. A model is proposed for the evolution of this particular Middle East area, in which the Dead Sea Transform shows a strong deviation relative to its main north–south orientation.

Abstract The aim of these investigations was to revise the geological map of Lebanon. Calcareous nannofossils were studied from a predominantly marly Senonian–Maastrichtian and Cenozoic series. About 900 spot samples were collected from exposed strata. This lithologically homogenous stratigraphic interval is poorly subdivided on the existing geological maps. The present study allows the precise determination of hiatuses and tectonic events. Palaeocene, Upper Eocene, Upper Oligocene, and Lower Miocene units were identified for the first time in Lebanon.

Abstract We associate a brittle tectonic analysis and a stratigraphic study of the NW Arabian platform in Syria in the northern Coastal Range, Lattakia basin, and Baer-Bassit areas. These complementary approaches allowed characterizing the tectonic and palaeostress evolutions of this region since the Late Cretaceous. In Mesozoic and Palaeogene, before the Arabia–Eurasia collision, essentially developed extensional tectonics. A major extensional phase, characterized by a NE–SW directed extension, was recognized during the Senonian. It is associated with the activity of the Euphrates graben. The Eocene–Oligocene period is marked by a north–south directed extension associated with minor east–west trending normal faults, associated with syn-depositional structures. The compressional deformation initiated at the end of Oligocene north of Baer-Bassit. The major phase of shortening is Early Miocene in age in NW Syria. The related brittle structures and folding were resulted from a 110°–135° oriented compression. During this event, the Baer-Bassit is thrusted over the Coastal Range platform along the SE vergent Lattakia thrust. This major thrusting induced the flexure of the Arabian platform and the formation of the Middle to Late Miocene Lattakia basin. From the end of the Miocene, and until Present, the region experienced a NNW–SSE directed regional compression. We also evidenced an east–west trending compression near the Dead Sea Fault (DSF) area, coeval with the NNW–SSE one, associated with the north–south folding of the Coastal Range. It likely corresponds to a stress-field deflection in relationship with the DSF activity. From latermost Miocene to Present, the left-lateral displacement along the northern segment of the DSF can be estimated to 30–40 km, from the offset of the Early Miocene deformation front.