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The Levant Basin of the Eastern Mediterranean accumulated voluminous siliciclastic sediments during the Oligocene–Miocene. The deep‐sea section has attracted significant interest as it contains world‐class hydrocarbon reservoirs ('Tamar Sands Play'). Our recent sandstone provenance study revealed that the hydrocarbon‐bearing, lower Miocene 'Tamar Sands' were recycled from older quartz‐rich sandstones that covered the Arabian flank of the Red Sea Rift. However, sandstones constitute just a third of the thickness of the Oligocene–Miocene siliciclastic section in the Levant Basin, with the rest being mainly composed of shales. Unravelling the provenance of the shale fraction is therefore essential for a comprehensive reconstruction of the Oligocene–Miocene source‐to‐sink system of the Levant Basin. In the present study, we examined the mineralogy and Sr‐Nd isotopes of clay samples retrieved from deep‐sea boreholes that penetrated the Oligocene–Miocene siliciclastic section. The isotopic composition of most clay fractions resembles that of Nile Delta sediments, indicating that unlike the 'Tamar Sands', their dominant provenance lay in NE Africa. Our investigations show that they were derived from Neoproterozoic basement rocks of the Arabian‐Nubian Shield and Tertiary continental flood basalts. The absence of chlorite and serpentine negates detrital contribution from the Arabia‐Eurasia suture in the north. Compilation of the available thermochronology data and major geologic events shows that the accumulation of the siliciclastic section in the Levant Basin coalesced with uplift of the continental areas around the Red Sea. The marked switch to shale deposition recognised in the basin during the late early Miocene signifies the downfall of the 'quartzose' Arabian sediment transport system, when it was partially captured by the evolving Dead Sea Transform valley. Our study highlights the strength of coupling sand and clay provenance investigations in source‐to‐sink studies of sedimentary basins. [ABSTRACT FROM AUTHOR]

The authors present new captures of three exotic teleost species in the Syrian marine waters. The first capture concerned a specimen of Dory snapper Lutjanus fulviflamma (Forsskål, 1775) which measured 222 mm total length (TL) and weighed 161 g. The second capture was a yellow bar angelfish Pomacanthus maculosus (Forsskål, 1775) which measured 245 mm total length and weighed 489 g. The third capture was a specimen of Emperor angelfish Pomacanthus imperator (Bloch, 1787) which measured 175 mm total length and weighed 456 g. These new captures suggest that viable populations of these three species are successfully established in the Syrian marine waters.

Abstract Methane‐derived authigenic seep carbonates occur globally along continental margins. These carbonates are important archives to identify seep dynamics, the source of the ascending methane‐enriched fluids together with their timing, and are an important carbon sequestration mechanism. Recently, seep carbonates were discovered in the Levant Basin in the south‐eastern Mediterranean Sea. To elucidate past seepage activity and dynamics across the basin, different seep carbonate morphologies (chimneys, crusts and pavements) retrieved from the Levant Basin were mapped based on remotely operating vehicle data and analysed using standard sediment petrographic techniques, X‐ray diffraction and stable carbon and oxygen isotope analyses. Carbonate chimneys consist of micrite (δ13CVPDB of −10‰ to +5‰) with dispersed baryte and dolomite crystals, fan‐shaped aragonite (δ13CVPDB of −52‰ to −30‰) and high‐magnesium calcite cements, with the latter often growing from low‐magnesium calcite spherules. Botryoidal low‐magnesium calcite cements are forming in small cavities. Carbonate crusts consist of micrite with low‐magnesium calcite breccias, high‐magnesium calcite nodules (δ13CVPDB of −35‰ to −20‰) and cements, and partially replaced fan‐shaped aragonite cements. Carbonate pavements consist of low‐magnesium calcite microsparite, micritic dolomite and high‐magnesium calcite. Fan‐shaped aragonite is locally present as pore‐lining cement. Iron oxides are often seen coating the low‐magnesium calcite, high‐magnesium calcite and dolomite cements. Chimneys and crusts, characterised by high amounts of high‐magnesium calcite and aragonite, are interpreted to have formed through advective methane fluxes. Pavements, with high quantities of dolomite, are explained as the product of diffusive methane flux. Sediment petrographic and geochemical analysis of the different carbonate morphologies and cement phases therein witness distinct modes of ascending fluid fluxes and their mixing with marine pore water and/or sea water during precipitation of the individual phases.

Copyright of Iraqi Journal of Aquaculture is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Methane‐derived authigenic seep carbonates occur globally along continental margins. These carbonates are important archives to identify seep dynamics, the source of the ascending methane‐enriched fluids together with their timing, and are an important carbon sequestration mechanism. Recently, seep carbonates were discovered in the Levant Basin in the south‐eastern Mediterranean Sea. To elucidate past seepage activity and dynamics across the basin, different seep carbonate morphologies (chimneys, crusts and pavements) retrieved from the Levant Basin were mapped based on remotely operating vehicle data and analysed using standard sediment petrographic techniques, X‐ray diffraction and stable carbon and oxygen isotope analyses. Carbonate chimneys consist of micrite (δ13CVPDB of −10‰ to +5‰) with dispersed baryte and dolomite crystals, fan‐shaped aragonite (δ13CVPDB of −52‰ to −30‰) and high‐magnesium calcite cements, with the latter often growing from low‐magnesium calcite spherules. Botryoidal low‐magnesium calcite cements are forming in small cavities. Carbonate crusts consist of micrite with low‐magnesium calcite breccias, high‐magnesium calcite nodules (δ13CVPDB of −35‰ to −20‰) and cements, and partially replaced fan‐shaped aragonite cements. Carbonate pavements consist of low‐magnesium calcite microsparite, micritic dolomite and high‐magnesium calcite. Fan‐shaped aragonite is locally present as pore‐lining cement. Iron oxides are often seen coating the low‐magnesium calcite, high‐magnesium calcite and dolomite cements. Chimneys and crusts, characterised by high amounts of high‐magnesium calcite and aragonite, are interpreted to have formed through advective methane fluxes. Pavements, with high quantities of dolomite, are explained as the product of diffusive methane flux. Sediment petrographic and geochemical analysis of the different carbonate morphologies and cement phases therein witness distinct modes of ascending fluid fluxes and their mixing with marine pore water and/or sea water during precipitation of the individual phases. [ABSTRACT FROM AUTHOR]

The tectonic setting of Lebanon in the eastern Mediterranean region is a restraining bend along the Dead Sea Transform Fault, which is the plate boundary between Arabia and Africa. Within the Lebanese Restraining Bend, the plate boundary splays into several fault branches that are mapped onshore Lebanon and known to have contributed to the evolution of the Lebanese structural framework. Different models have been proposed about the geological structures offshore Lebanon, and how those structures could relate to the onshore tectonics. Based on 2D seismic reflection data, a previously interpreted thrust fault system offshore Lebanon referred to as "Mount Lebanon thrust" was suggested to be responsible for the 9 July 551 M 7.2 earthquake, which was one of the most destructive in the history of the Levant. This thrust system has been accepted as the main structure behind the offshore seismic activity. The objective of this paper is to use current 3D seismic reflection data in order to interpret the main tectonic structures offshore Lebanon, and to differentiate features formed by tectonic activity from others caused by different mechanisms such as subsurface salt movement. Such information is very useful in understanding the tectonic framework of the region from the earthquake geology perspective. A bathymetric map of the Lebanese offshore area was generated and used to delineate the seafloor features. Major and minor faults were interpreted and used to identify and understand the behavior of potential tsunami-generating structures. After careful investigation of the offshore area using the available 3D seismic data, the authors were not able to confirm the existence of Mount Lebanon thrust. Instead, they propose that the Latakia ridge that lies between Lebanon and Cyprus is a major and prominent structure that can trigger high-magnitude tsunamigenic earthquakes. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of the environmental factors affecting the ecology of seaweed (macroalgae) populations in the Levant Basin, attempting to identify both similar and different factors that determine distribution. Using correspondence analysis (CA) the study found a significantly similar pattern in the relations between countries and macroalgae – both for the whole group and within each phylum: Chlorophyta, Ochrophyta, Rhodophyta. The study identified two different macroalgae populations in the Levant Basin: The easternmost group living in open water off the coasts of Syria, Lebanon and Israel, and the shell group found in more sheltered waters in Egypt, Turkey, the Turkish Republic of Northern Cyprus, and Republic of Cyprus (Greece Cyprus): south Cyprus; and the North Cyprus. The differences between the two communities can be explained by dynamic wave activity. Following a taxonomic and nomenclatural revision according to AlgaeBase, of 693 species to date recorded from the studied area, only 573 species remained. 26 of them appear in all 7 countries and other 68 in 6 countries. 204 species appear in only one country. 3 or 4 species have only been described in the Middle East and could be endemic. [ABSTRACT FROM AUTHOR]

Ichthyoplankton surveys hold much potential for studying fish biodiversity, but challenges and uncertainties in identification of early life stages and the drifting of planktonic eggs and larvae limit the efficacy of this method. In this study, we investigate mesopelagic fish biodiversity in Antalya Bay in the Northeastern Mediterranean Sea, based on ichthyoplankton samplings in combination with integrative taxonomy and particle backtracking simulations to overcome the forementioned limitations. We morphologically identified early life stages of 26 mesopelagic species and the identification of 17 of them was validated using DNA barcoding. With 13 species identified, Myctophidae was the most diverse family. Larvae of Cyclothone braueri Jespersen & Tåning, 1926, Diaphus holti Tåning, 1918, Ceratoscopelus maderensis (Lowe, 1839) and Cyclothone pygmea Jespersen & Tåning, 1926, constituted the most dominant species in the study area. Based on larval samples, we provided the first record of Paralepis coregonoides Risso, 1820, the first substantiated records of Vinciguerria poweriae (Cocco, 1838) and Hygophum hygomii (Lütken, 1892) and the second record of Evermannella balbo (Risso, 1820) off the Turkish coasts of the Mediterranean Sea. Particle backtracking simulations revealed that the spawning grounds of these species were in Antalya Bay, suggesting that there were reproducing populations of these species off the Mediterranean coast of Turkey, although these were not properly documented before the present study. Our results demonstrate that ichthyoplankton surveys can provide a reliable practice to study the biodiversity of understudied and difficult to access fish groups when combined with molecular identification techniques and particle backtracking simulations. [ABSTRACT FROM AUTHOR]

In the last two decades, major taxonomic modifications have taken place on marine macroalgae with important changes at the genera level and discovery of cryptic species worldwide. These updates have an important role by serving as a baseline for future ecological interpretations related to on-going climate changes in the marine environment. Hence, this study aimed to elaborate a comprehensive and revised checklist of seaweeds and seagrasses reported in the literature over the years for Syrian Mediterranean Sea shorelines. It was found that the marine flora is quite diverse with a recounted total of 290 species of which 52 are Chlorophyta, 178 Rhodophyta and 60 Ochrophyta (Phaeophyceae). The Syrian shores also host five marine angiosperms (seagrasses), even though Zostera marina Linnaeus has been unaccounted for in recent years. This study will further contribute to a better understanding of seaweed distribution within the Levant basin. [ABSTRACT FROM AUTHOR]

On 29 May 2022, two specimens of Baillon's wrasse, Symphodus bailloni (Valenciennes, 1839) were captured from the coast of Syria (eastern Mediterranean Sea). Sampled two specimens of S. bailloni were measured at 117 and120 mm in TL and weighed 25.7 and 23.2 g. These findings is the first records of this species in the Levant Basin, and the easternmost extension range of the species in the Mediterranean Sea. Symphodus bailloni is not a herculean or Lessepsian migrant but should be considered as a permanent resident of the Mediterranean basin despite the fact not largely distributed. [ABSTRACT FROM AUTHOR]

On 16 June 2022, two specimens of Pomacanthus maculosus (Forsskål, 1775) were observed in the Syrian marine waters. One specimen was captured and classified, measured, preserved in formaldehyde and deposited at Tishreen University. It is a second substantiated record in the Levant Basin, and the first for the Syrian coast. The successful establishment of a viable population of P. maculosus in the Mediterranean Sea remains a suitable hypothesis which cannot be totally ruled out. [ABSTRACT FROM AUTHOR]

A specimen of slender goby Gobius geniporus Valenciennes, 1837 was caught on 21 February 2021, from the Syrian coast at a depth of 13 m. This specimen measured 87 mm in total length and weighed 6.89 g. The present finding represents the first record of G. geniporus from the Syrian coast and confirms the species occurrence in the Levant Basin, eastern region from the Mediterranean Sea. [ABSTRACT FROM AUTHOR]

This paper analyzes hydrocarbon accumulation conditions, defines hydrocarbon plays and discusses their hydrocarbon accumulation models using geological and geophysical data and an international petroleum exploration and production database, with an approach of integrated geological investigation and play quick analysis. The intention is to identify favorable areas for exploration in the Levant Basin which experienced three main tectonic evolution stages, including rifting, passive continental marginal and tectonic inversion. It can be divided into three plays in Miocene, Pliocene and Mesozoic reservoirs. The Miocene play is the most important. The controlling factors of Miocene play are Oligocene-Miocene biogenic gas, high-quality submarine fan turbidite sand reservoir that related to Palaeo-Nile drainage system, large-scale anticline traps formed during tectonic inversion and Messinian evaporite as a regional caprock. High-quality channel turbidite sand reservoirs related to small-medium sized submarine canyons and short-distance gas migration are key factors that control hydrocarbon accumulation of the Pliocene play. Potential Cretaceous deepwater clastics and Jurassic carbonate build-ups on highs comprise a speculative Mesozoic play in deep water. Three plays are favorable regimes for future exploration, and the Miocene play in deep water and the under-explored Mesozoic regime are of high exploration potential.

An extensive sedimentary-rock basin is located within the continental margin of the Levant, where, since 2008, numerous natural gas fields have been discovered, including Tamar, Tannin, Dalit and Leviathan in the offshore zone of Israel, and Aphrodite in the zone of economic interests of Cyprus. Deposits of biogenic methane, located in the deep-water Levantine depression, are confined to terrigenous sandstones of late Oligocene-Early Miocene age. The discovery of another gas field Zohr in 2015 in the area of the underwater uplift of Eratosthenes caused a real boom among petroleum geologists. The fact is that natural gas deposit with reserves of about 30 trillion cubic feet is not in the terrigenous, but carbonate reservoir of the reef genesis, which opens significant prospects for the discovery of new large gas accumulations in the area of this major uplift. All the above-mentioned deposits are located in the same range of sea depths (1600-2000 m) in the propagation zone of the Messinian evaporites, that serves as a regional screen. An analysis of the materials currently published suggests that in the epochs of the sediments formation in which gas deposits are located, the depths of the seabed in the southern regions of the Levant depression were significantly lower compared to modern ones. Currently, there is no doubt that in the Levant region there is the largest gas-bearing basin in the Mediterranean region, with gas reserves of several hundred trillion cubic feet.

Salt basins often exhibit a shelf/slope region of extension and a deeper domain of contraction. The up‐slope normal faults in such salt tectonics systems are often associated with the pinch‐out edge of the buried salt layer. Although the spatial correlation between the normal faults and the salt pinch‐out was previously observed, the mechanism was not fully explained. The Levant basin, which is a young and mildly deformed salt basin with a relatively thin overburden, provides an opportunity to analyze a simple salt tectonics system driven by basin margin tilt, and the formation of the normal faults. This work presents analytical and numerical modeling of the coupled viscous salt and overlying visco‐plastic sediment layer. Results suggest the viscosities of both the sediment overburden and salt, as well as their thicknesses, control the deformation of the coupled layers. The visco‐plastic deformation mechanism explains quantitatively the position of faulting and observations of the temporal evolution of brittle deformation in the Levant basin margin. It predicts that the largest stress in the overburden arises above the salt edge, driving normal faulting at that location. Our model also places quantitative constraints on the effective viscosity of the overburden (>2 × 1020 Pa s), which is consistent with experimentally‐determined creep laws. Our results contribute to the understanding of halokinematics in salt basins during the early stages of deformation and will allow better assessment of geological hazards related to salt related deformation. Plain Language Summary: A salt basin is a down‐dropped block of the earth's crustal rocks, in which past evaporation of sea‐water caused deposition of a thick layer of salt and evaporites. For example, during the "Messinian salinity crisis", about 6 Myr ago, the Mediterranean sea partially or fully evaporated, depositing a thick layer of salt. This salt layer got progressively buried under sediments, deep beneath the seafloor. Since such geologically buried salt layers flow like viscous fluids under the weight of accumulated sediments, salt motion often leads to breakage of overlying rock layers. We used combined solid‐fluid mechanics‐based computer and theoretical models to explain and predict the location and timing of such salt‐flow induced sediment breakage. Our work focuses on locations near the edge of the salt, showing that this location is especially prone to breakage (faulting), and explaining the mechanical reason for that. We finally use our model results to explain and predict the timing and locations of faults that are observed near the Israeli shore. Key Points: We simulate and predict the formation of normal faults due to tectonic tilting of the shelf/slope region of a salt basinThe viscosities and thicknesses of the salt and the sediment overburden layers control fault initiationThe predicted faulting process agrees with observations of location and temporal evolution of normal faulting in the Levant basin margin [ABSTRACT FROM AUTHOR]

Copyright of Ege Journal of Fisheries & Aquatic Sciences (EgeJFAS) / Su Ürünleri Dergisi is the property of Ege Journal of Fisheries & Aquatic Sciences (EgeJFAS) / Su Urunleri Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Isolated, Miocene continental basins scattered over Israel and Jordan represent the remnants of a continental‐wide fluvial system, which originated in Arabia and transported siliciclastic sediments westward to the deep Levant Basin. These basins define two geographically separated sedimentary provinces. The detrital zircon age spectra in both provinces are dominated by Neoproterozoic U‐Pb ages (550–1,000 Ma), resembling those of Paleozoic‐Mesozoic sandstones exposed along the uplifted Red Sea Rift flank. However, while the southern province exhibits two prominent peaks at ~600 and ~1,000 Ma, similar to those seen in Cambrian‐Ordovician sandstones in southern Israel and Jordan, the northern province shows an additional significant age peak at ~800 Ma and its overall spectrum resembles that of Devonian sandstones in northern Saudi Arabia. These variations distinguish the two Miocene clastic outliers as pertaining to two separate, NW‐directed transport systems delivering siliciclastic sediments from Arabia towards the deep Levant Basin. The detrital zircon U‐Pb‐Hf signal of the Israeli Miocene clastic units differs from that of the River Nile, particularly in the lack of Cenozoic‐Mesozoic‐aged zircons in the former. This allows us to distinguish the properties of the fluvial system that existed in Arabia, on the eastern side of the Red Sea, from that of the River Nile that drained its western flanks. While it is commonly accepted that the (proto‐)Nile River played a key role in the Levant Basin fill, the eastern fluvial system that prevailed on the Arabian side may have been also important. [ABSTRACT FROM AUTHOR]

The role of detrital components influencing the petrophysical parameters of calcareous rocks is primordial for understanding its effect on the porous space, which in turn control reservoir quality. Long (340 m) core encompassing Eocene carbonate sediments from the Negev area has been made available for conducting petrophysical analyses. The sequences investigated comprised the Paleocene to early Eocene age mainly composed of hemipelagic sediments of the Taqiye formation in the Negev, southern Israel. The sedimentary record separated into three zones (zones 1 to 3) based on variations in the lithology and petrophysical properties (density, magnetic susceptibility, and sonic velocity). The significant differences in the petrophysical parameters occur in lowermost zone 1 (Late Paleocene), which displayed erratic variations in measured sonic velocity, density, magnetic susceptibility, porosity, and insoluble residual contents higher than 10%. Zone 1 is primarily composed of intercalation of dark gray clay, hard white chalky limestone, and dark gray marl, with smectite as the dominant clay mineral. The overlying zones 2 and 3 (Early to Middle Eocene) are mainly composed of dark chalky limestone with some chert units, occasionally intercalated with gray chalky limestone. The petrophysical and lithological properties in these two zones gradually increase with depth according to a decreasing trend in porosity. The main factors influencing variations in the petrophysical parameters are the presence of clay content and carbonate dissolution. The depositional environment is predominantly composed of terrigenous sediments, and the deeper buried calcareous clay lithology derived from the overlaid sediments. The source of high magnetic susceptibility values observed in zone 1 is unclear. We have developed a useful empirical relation for the prediction of acoustic impedance in pure carbonate sediments. This study has produce, for the first time, critical high-resolution insights into the petrophysical properties of Eocene deposits from the northern Negev in southern Israel. [ABSTRACT FROM AUTHOR]

The striped piggy, Pomadasys stridens (Forsskål, 1775), is a recent invasive fish species in the eastern Mediterranean. Although its population dynamics was investigated in detail in its natural distribution area, the western Indian Ocean, an important data gap still exists in the Mediterranean. This study was carried out to determine the growth, mortality, and the length-weight and length-length relations of invasive striped piggy right after its establishment in the area. Samples were collected seasonally between April 2014 and December 2015 by using bottom trawl from 10 and 20 m depth contours off the north-western coast of the Gulf of Iskenderun. After the length, weight, and sex of fish were recorded, sagittal otoliths were extracted and examined for age determination. Then length-length, length-weight, and length at age relations, growth performance, and mortality rates were calculated for both sexes and pooled data. In the study, a total of 1131 individuals were investigated, the total length of which ranged between 7.3 and 18.9 cm. The mean length was 12.32 ± 0.11 cm. There was no significant difference between the length-weight relation (LWR) parameters of sexes and pooled data. The overall LWR was found to be TW = 0.0113 * TL^3.096 in all specimens. The von Bertalanffy growth parameters were not significantly different between males and females. The model parameters for both sexes were L∞ = 22.01 cm, K = 0.22 years-1, t0 = -1.30 years. The growth performance index (Ø') was calculated as Ø' = 2.03. For combined sexes, the total, natural and fishery mortality rates were Z = 1.14 years-1, M = 0.66 years-1, and F = 0.48 years-1, respectively. The exploitation rate of the stock was found to be E = 0.42. The growth performance of the invasive striped piggy population was determined to be similar to the ones reported from the Gulf of Suez where was the closest natural distribution area of the species. Although striped piggy is proper for human consumption and commercially caught in its native range, its fishery has not yet been established in the Eastern Mediterranean and we found that there was insufficient fishery pressure on the invasive population. [ABSTRACT FROM AUTHOR]

Blunthead puffer Sphoeroides pachygaster (Müller and Troschel, 1848) is a circumglobally distributed Tetraodontid found in temperate and tropical waters. It is believed to have colonized the Mediterranean Sea from the Atlantic Ocean. There are relatively few records of this fish in the Mediterranean Sea. On March 2020, a mature female individual was caught incidentally by a commercial fisher in Northern Cyprus. The fish was 520 mm in total length and 1200 grams in total weight. Detailed morphometrics and meristics were reported. This study is the first substantiated record of S. pachygaster from Cyprus waters, and the specimen is the largest blunthead puffer reported with a 455 mm standard length and 520 mm total length. [ABSTRACT FROM AUTHOR]

At present, salt tectonics in the Levant Basin comprises extension along the continental slope and folding and thrusting in the deep basin. However, here we show that the shape, the age, and the amplitude of deformation in the extensional and contractional domains do not fit the paradigm of "updip extension and downdip contraction." Deep basin shortening is not parallel to continental margin extension; it is younger and stronger. We propose that while extension of the Levant continental slope is an expression of basinward gliding, the deep basin shortening belongs to the circum‐Nile deformation belt (CNDB) propelled by out‐squeezing of salt from under the Nile delta. However, despite the independent driving forces, the two deformation systems seem to affect each other. In the southern part of the basin where the two systems meet, the NW gliding of the continental slope is restrained by the NE motion of the CNDB and vice versa. Interestingly, the beginning of folding along the CNDB (~2 Ma) coincides with the establishment of a continental shelf offshore Israel. We thus propose that these two apparently independent phenomena express maturity of the Nile delta that had reached a size and shape sufficient to trigger salt out‐squeezing and to form a continuous continental shelf from the Nile to Israel. This continuity allowed shelf alongshore sediment transport that further propagated the Israeli shelf northward and westward. Key Points: The salt tectonics paradigm of "updip extension and downdip contraction" doesn't fit the thin‐skinned deformation in the Levant BasinSlope extension is caused by basinward tilting, while deep basin shortening is caused by salt out‐squeezing from under the Nile deltaInitiation of a continental shelf offshore Israel coevally with deep basin folding suggests a common origin of Nile delta maturity [ABSTRACT FROM AUTHOR]

Understanding continental‐slope morphological evolution is essential for predicting basin deposition. However, separating the imprints and chronology of different seafloor shaping processes is difficult. This study explores the utility of bathymetric spectral decomposition for separating and characterizing the variety of interleaved seafloor imprints of mass wasting, and clarifying their role in the morphological evolution of the southeastern Mediterranean Sea passive‐margin slope. Bathymetric spectral decomposition, integrated with interpretation of seismic profiles, highlights the long‐term shape of the slope and separates the observed mass transport elements into several genetic groups: (1) a series of ~25 km wide, now‐buried slide scars and lobes; (2) slope‐parallel bathymetric scarps representing shallow faults; (3) slope‐perpendicular, open slope slide scars; (4) bathymetric roughness representing debris lobes; (5) slope‐confined gullies. Our results provide a multi‐scale view of the interplay between sediment transport, mass transport and shallow faulting in the evolution of the slope morphology. The base of the slope and focused disturbances are controlled by ~1 km deep salt retreat, and mimic the Messinian base of slope. The top of the open‐slope is delimited by faults, accommodating internal collapse of the margin. The now‐buried slides were slope‐confined and presumably cohesive, and mostly nucleated along the upper‐slope faults. Sediment accumulations, infilling the now‐buried scars, generated more recent open‐slope slides. These latter slides transported ~10 km3 of sediments, depositing a significant fraction (~3 m in average) of the sediments along the base of the studied slope during the past < 50 ka. South to north decrease in the volume of the open‐slope slides highlight their role in counterbalancing the northwards diminishing sediment supply and helping to maintain a long‐term steady‐state bathymetric profile. The latest phase slope‐confined gullies were presumably created by channelling of bottom currents into slide‐scar depressions, possibly establishing incipient canyon headword erosion. [ABSTRACT FROM AUTHOR]

In this study, we document the introduction of the Australian endemic Istiblennius meleagris into the Mediterranean Sea, probably via shipping, and its expansion along the Israeli coastline. Taxonomic confirmations were based on both morphological and molecular approaches. This is the first evidence of a non-indigenous benthic fish colonizing the rocky intertidal zone in the eastern Mediterranean, thus raising concerns regarding the future integrity of the native fish community in this ecosystem. [ABSTRACT FROM AUTHOR]

Deep and long-lived rifted basins host valuable information about tectonic evolution and environmental changes occurring in their surroundings throughout hundreds of millions of years. These basins, however, are hard to infer, because their deep parts are commonly obscured in seismic images and their structure is affected by several deformation phases that occurred during their long history. The Levant Basin is a good example for a deep Tethyan basin that formed alongside Gondwana breakup. Unlike many Tethyan basins that were eroded and/or severely deformed during the Alpine orogeny, the Levant Basin has preserved a thick (>15 km), long-lived (>250 Myr), and continuous sedimentary record providing a world-class archive to study the role of post-rift subsidence and sediment supply on depocenter evolution. It exemplifies classic tectono-sedimentary problems, such as basin inversion and the mutual relationships between accommodation space, sediment supply, and sediment accumulation. Also, it provides valuable information about the ancient Tethyan margin, which were mostly destructed by the Alpine Orogeny. We review the tectonic and sedimentary evolution of the Levant Basin. We synthesize regional seismic interpretations from previous studies utilizing thousands of kilometers of seismic lines and tens of wells in a unified dataset. Based on thickness analysis, we identify the syn -rift to post rift transition. The regional seismic horizon marking this transition is tied to dated horizons in wells providing a concrete age constraint of pre- 163 Ma (end of Callovian) for the end of rifting, which was previously debated. In addition, we show that rifting comprises at least two phases, which are equivalent to two extensional phases documented onshore: Permian to Middle-Triassic and late-Early to Middle-Jurassic. We further show that the early extensional structures (normal faults) approximately coincide with much younger contractional structures of the Syrian Arc Fold belt. Analysis of 11-thickness maps showcase the 250 Myr evolution of sedimentary filling, opening a discussion about what controlled depocenter migration in relation to tectonic subsidence and sediment supply. We distinguish between periods during which near margin accumulation dominated versus periods during which more sediments accumulated in the deep basin. We explain these changes in light of sediment sources in surrounding continents and paths of transport. Marginal accumulation periods (syn -rift, early post-rift, and Pliocene-Quaternary) represents sediment supply from the nearby Levant (Arabia), whereas, deep basin accumulation periods represent sediment supply that was either provided from the water column (pelagic micro- and nano-fossils, Santonian to Mid-Eocene), or transported mostly from Africa with minimal accumulation along the Levant margin (during the Late-Eocene to Miocene). This review is based on holistic approach for basin analysis. A lateral perspective integrates seismo-stratigraphic information from the deep basin with lithological and paleo-geographical information from nearby continental areas. A vertical perspective ties deep basin structures formed during rifting with shallow structures formed much later during contraction. Structural maps are used to highlight horsts, folds, and canyons, whereas thickness maps are used to highlight patterns of sediment accumulation. Finally, the distinction between distal basin and marginal accumulation is interpreted in light of the regional geology hinting for sediment sources. • The syn - to post-rift transition constrains the end of rifting to <163 Ma. • Two phases of rifting are identified consistent with onshore data. • Interplay between early rifting and later shortening is demonstrated. • 11 isopach maps document basin evolution alongside regional tectonic processes. • We distinguish between distal-basin-accumulation and continental-margin-accumulation. [ABSTRACT FROM AUTHOR]

This paper reports the range extension of Kyphosus vaigiensis in the northeastern (NE) Mediterranean. On 18 November, 2018, a single specimen of K. vaigiensis was caught in İskenderun Bay (36°45.6′ N, 35°40.8′ E) by a recreational fisherman and reported through a social media application. The specimen was identified using morphological and molecular methods. Its occurrence and distribution in the NE Mediterranean were investigated based on interviews with fishers. [ABSTRACT FROM AUTHOR]

The Pope's ponyfish Equulites popei (Whitley, 1932) is a marine fish native to the wide Indo-Pacific area and is considered an alien species in the Mediterranean Sea. A total of 10 individuals were collected, in May 2019, from Antalya Bay (Turkey, northwestern Levant Basin). These records represent the westernmost occurrence of the fish in the Mediterranean Sea. We also provide information on its catch per unit area (27 ind.km-2) and the maximum depth of its occurrence (150 m) in the Mediterranean Sea. [ABSTRACT FROM AUTHOR]

The Eastern Mediterranean Levant Basin is a proven hydrocarbon province with recent major gas discoveries. To date, no exploration wells targeted its northern part, in particular the Lebanese offshore. The present study assesses the tectono‐stratigraphic evolution and related petroleum systems of the northern Levant Basin via an integrated approach that combines stratigraphic forward modeling and petroleum systems/basin modeling based on the previous published work. Stratigraphic modeling results provide a best‐fit realisation of the basin‐scale sedimentary filling, from the post‐rift Upper Jurassic until the Pliocene. Simulation results suggest dominant eastern marginal and Arabian Plate sources for Cenozoic siliciclastic sediments and a significant contribution from the southern Nilotic source mostly from Lower Oligocene to Lower Miocene. Basin modeling results suggest the presence of a working thermogenic petroleum system with mature source rocks localised in the deeper offshore. The generated hydrocarbons migrated through the deep basin within Jurassic and Cretaceous permeable layers towards the Latakia Ridge in the north and the Levant margin and offshore topographic highs. Furthermore, the basin model indicates a possibly significant influence of salt deposition during Messinian salinity crisis on formation fluids. Ultimately, the proposed integrated workflow provides a powerful tool for the assessment of petroleum systems in underexplored areas. [ABSTRACT FROM AUTHOR]

In this study, analyses of a high-resolution, three-dimensional seismic reflection dataset and well-log data were combined to characterise a distinct Pliocene interval in the Levant Basin offshore central Israel. This succession is characterised by moderate to high-amplitude, discontinuous to continuous seismic reflections between a mass transport deposit above and an undeformed basin series below. The studied interval contains two separate channelised subunits, which predated the salt related deformations. Morphologically, the channels trend in a north to northwest direction, are incised <50 m, are ~50 m to 350 m wide and increase in number from base to top. A vertical variation in channel morphology style and stratigraphic organization is identified. The lower part of each subunit is dominated by coarser grained, narrow V-shaped channels (average width <120 m and low sinuosity, <1.06). In contrast, the upper part of each subunit is predominantly fine-grained and U-shaped with relatively wide channels (average width >230 m and higher sinuosity, >1.1). The mechanisms that control the interplay between sedimentary processes and channel evolution show a cyclic pattern. Due to the cyclic occurrence of different channel types and the estimated age of the studied interval, formation and evolutionary processes of the submarine channels in the study area are likely to be controlled by relative sea level fluctuations and increased Nile River sediment supply, which is associated with rapid uplift of the Ethiopian plateau and increased African Monsoon rainfall during the Pliocene. [ABSTRACT FROM AUTHOR]

Petroleum exploration activity in the deep basins of the Eastern Mediterranean has been rejuvenated over the last decade with the discoveries of the giant Tamar and Leviathan gas fields made by Noble Energy and its partners, and more recently with the discovery of the Zohr field by Eni. With exploration efforts pursuing deeper and older leads, a first-principles quantitative study of the region seems timely. While it is generally agreed that the Levant Basin formed along the northern passive margin of Gondwanaland during the Early Mesozoic, its complex post-rift evolution has not been documented in detail. Located in a unique junction of three active tectonic plates and at the distal end of the Nile, one of the largest rivers on Earth, the Levant Basin is characterized by a thick sedimentary section, more than half of which has accumulated since the Oligocene, in the last ∼15% of its existence. This study implements a quantitative basin-modelling workflow that assesses the three-dimensional crustal geometry of the Levant Basin and its post-rift evolution, by integrating 3D-gravity-inversion and 3D-flexural-backstripping techniques. The focus of the gravity inversion, which includes corrections for the lithosphere thermal gravity anomaly resulting from lithosphere thinning and for the magmatic addition from decompression melting, has been to predict both the 3D crustal-structure and the magnitude of total lithospheric stretching for the Levant Basin. The 3D-flexural-backstripping workflow, using the outputs of the gravity inversion, invokes three major processes in its calculations, accompanying the layer-by-layer removal of the stratigraphy: (i) 3D flexural-isostatic unloading, (ii) decompaction in response to the removal of overburden and (iii) reverse thermal-subsidence modelling, controlled by the stretching factor derived from the gravity inversion. Backstripping has produced a series of maps and cross sections depicting the evolution of post-rift palaeobathymetry in the Levant Basin. The integration of these techniques allows us to assess the evolution of the basin and the various sedimentary and tectonic events that have occurred since basin initiation. Although the calculated stretching factors indicate that while the lithosphere underlying the Levant Basin has been very highly stretched and thinned, the stretching did not progress to the formation of new oceanic crust. Predicted palaeobathymetry portrays a thermally-subsiding basin reaching maximum water-depths at the onset of the Cenozoic. This deep basin provided ample amount of accommodation space for the large volumes of terrigenous clastics, sourced from the contemporaneous uplift and exhumation of the basin margins and delivered in large part, at least since the Oligocene, by the continental drainage of the Nile. These sediments have been filling and shallowing the basin ever since. The basin evolution described here is consistent with available geophysical and geological data and has important implications for petroleum-systems modelling within the basin. [ABSTRACT FROM AUTHOR]

Large parts of the Mediterranean were formed during the Mesotethys Ocean opening and subsequently became land-locked in the midst of the Africa-Eurasia plate convergence. Since the Neogene, this convergence has concealed key sections of the original basins. Previous studies widely agree that the easternmost part of the Mediterranean, the Levant Basin, opened during the Permian to Early Jurassic (PJ) and accordingly explain the architecture of the basin and its margins. However, since the PJ model was suggested in the late 1990’s a flood of new evidence has arrived since the hydrocarbon exploration, some of which do not fit in with the PJ model, and some remain unexplained. The current research re-examines the old and new evidence from the Levant basin, its margins, the surrounding landmass, the adjacent Eratosthenes Seamount and the eastern part of the Herodotus Basin. The integration of geological and geophysical data suggests that the Levant Basin formed ~100 Myr later than previously thought, i.e., during the Cretaceous. Its opening was triggered by the ‘Levant-Nubia' mantle plume that induced a sequence of wide-spread Ocean Island Basalt volcanism. The resulting crustal updoming and stretching led to the breakup of the Levant landmass since ~141 Ma, and drifting of the Eratosthenes Seamount since ~125 Ma. Back-arc extension shaped the Levant Basin as a hybrid crust comprising continental slivers intervened by oceanic patches. The basin opened during the Long Normal Cretaceous Polarity Chrons between ~122 and ~84 Ma, and therefore it does not show any magnetic lineation. The opening of the Levant basin occurred while the Herodotus basin floor subducted eastward under the Eratosthenes Seamount. The subduction hinge did a roll-back and facilitated the Seamount drifting. The Seamount absorbed intensive volcanism while chasing the subduction roll-back and sliding between two Subduction-Transform Edge Propagator (STEP) faults that bounded the stretching Levant back-arc basin. The Turonian-Maastrichtian compression stress regime, or inversion, halted the extension of the Levant Basin, stagnated its hybrid fabric, and prevented the development of a spreading center. The evolutionary scenario suggested here is a game changer for future exploration in the Levant and may serve as a global analog for the formation of marginal seas. [ABSTRACT FROM AUTHOR]

The present paper reports the first record of Adriatic sole Pegusa impar (Bennett, 1831) from the Syrian coast. This record confirms the occurrence of the species in the Levant Basin but does not suggest that a viable population is successfully established in this region. Its rarity in the area is probably due to misidentifications with other congeneric species. [ABSTRACT FROM AUTHOR]

Abstract: To date, little is known about the larval‐fish assemblages (LFAs) in the eastern Mediterranean. The purpose of this study is to investigate the intra‐annual variations of LFAs with an emphasis on the effects of physical, chemical, biological and meteorological conditions in the gulf of Iskenderun, which is a shallow (100 m maximum depth), semi‐enclosed bay located in the northeastern corner of the Mediterranean. The gulf is under the influence of offshore waters throughout the year. The study was based on an ichthyoplankton survey program performed at 28 stations over 12 months, between November 2009 and October 2010. During the study, a total of 11,411 larval individuals belonging to 177 taxa were sampled. The jackknife estimate of maximum species richness was 225 ± 19 for the study area. The maximum larval richness (84 species) and abundance (827 larvae/10 m2) values coincided with spring bloom in April. Gobiids dominated the ichthyoplankton of Iskenderun Bay by constituting 9% of species richness and 42% of total individuals. Four LFAs were identified which were in early winter (November to January), late winter (February and March), spring (April to June) and summer (July to October). The intra‐annual variations of richness, abundance and composition of ichthyoplankton were significantly correlated with the temperature and mesozooplankton biomass. The wind conditions and thermal stratification were also significantly correlated with the composition of LFAs. In conclusion, phenology of LFAs were formed under the influence of physical and tropho‐dynamic conditions in Iskenderun Bay, Northeastern Mediterranean. [ABSTRACT FROM AUTHOR]

This paper presents a new interpretation of the Levant margin, offshore Lebanon, with a review of Lebanese onshore geology and a new evaluation of the petroleum systems of the Eastern Mediterranean. Here, we divide the Lebanese onshore and offshore into four domains: the distal Levant Basin, the Lattakia Ridge, the Levant margin, and the onshore. Each domain is characterised by a particular structural style and stratigraphic architecture, resulting in different source‐reservoir‐trap configurations. This new division draws attention to specific areas of exploration interest in which there are distinct petroleum systems. Following a review of previously published data, this study presents new results from stratigraphic, structural and geochemical investigations. The results include a new interpretation of the Levant margin, focussing on the carbonate‐dominated stratigraphy of this area and its petroleum potential. New petroleum systems charts are presented for each of the four domains to refine and summarize the updated geological knowledge. [ABSTRACT FROM AUTHOR]

High-resolution seismic reflection and bathymetry data are analyzed to investigate the subsurface configurations promoting fluid escape along the Palmachim disturbance; a 20 km × 10 km gravitational collapse structure, offshore southern Israel. The dataset reveals seabed pockmarks with diameters ranging between 200 and 500 m, and depth of <50 m. A significant number of the pockmarks are located along ridge-like structures associated with compression, while an outlier is proximal to a turbidite channel. Seismic attribute analyses reveal a series of fluid-related amplitude anomalies within Quaternary sediments. We propose the onset of subsurface fluid flow to be synchronous with the evolution of the Palmachim disturbance, which was likely triggered by local seismicity. Our results suggest fluids from pre-Messinian strata exploited deformational pathways in the overburden to reach shallower levels where they were sequestered and redistributed in transient reservoirs (mass-transport complexes and channel-levee complex). The fluids are either focused toward the seafloor for expulsion or migrating into the ridges, providing four-way closure and accommodation. However, the fluids may also have no (pre)Messinian component, being locally sourced biogenic methane within the channel-levee complex. Under both scenarios, elevated pore-pressure resulted in hydrofracturing of the seafloor sediment and expulsion of fluids creating the pockmarks. The discovery of enhanced fluid escape through the Palmachim disturbance represents a new source of global methane not previously accounted for in carbon budgets from this region of the Mediterranean Sea. [ABSTRACT FROM AUTHOR]

Stratigraphic interpretation of twenty-four 2D seismic reflection profiles coupled with available well data from the Ocean Drilling Program (ODP) offshore Cyprus enabled identification of the main unconformities and the seismic packages in the western part of the Levant Basin and their correlation with major geodynamic events. The basic concepts of seismic stratigraphy were applied to improve our understanding of the tectonostratigraphy and the sedimentary architecture of Eratosthenes isolated carbonate platform. This platform is composed of dominant retrograding and aggrading Mesozoic carbonate build-ups and its evolution partly resembles that of the Egyptian margin. Deep-water mixed carbonates and siliciclastics probably prevailed in the basin during the Early Cretaceous. During the Late Cretaceous, these platforms were drowned. Following the convergence of the two plates, both the Eratosthenes Seamount (ESM) area and the Levant Basin progressively became part of a foreland basin along the Cyprus Arc. Different units in the Eratosthenes carbonate platforms (ECPs) and the transition to the deep Levant Basin are detailed here for the first time. We present a 3D conceptual model for the evolution of the western margin of the Levant Basin. We discuss the effect of the Miocene collision between the Cyprus Arc and Eratosthenes to understand the presence of upper Miocene Mass transport complexes (MTCs) in the deep basin and the tilting of the top of the adjacent ECPs. We briefly examine the deformation mechanisms of the Messinian salt near the paleo-shelves of the ECPs. [ABSTRACT FROM AUTHOR]

To estimate the potential inventory of natural gas hydrates (NGH) in the Levant Basin, southeastern Mediterranean Sea, we correlated the gas hydrate stability zone (GHSZ), modeled with local thermodynamic parameters, with seismic indicators of gas. A compilation of the oceanographic measurements defines the >1 km deep water temperature and salinity to 13.8 °C and 38.8‰ respectively, predicting the top GHSZ at a water depth of ~1250 m. Assuming sub-seafloor hydrostatic pore-pressure, water-body salinity, and geothermal gradients ranging between 20 to 28.5 °C/km, yields a useful first-order GHSZ approximation. Our model predicts that the entire northwestern half of the Levant seafloor lies within the GHSZ, with a median sub-seafloor thickness of ~150 m. High amplitude seismic reflectivity (HASR), correlates with the active seafloor gas seepage and is distributed across the deep-sea fan of the Nile within the Levant Basin. Trends observed in the distribution of the HASR are suggested to represent: (1) Shallow gas and possibly hydrates within buried channel-lobe systems 25 to 100 mbsf; and (2) a regionally discontinuous bottom simulating reflection (BSR) broadly matching the modeled base of GHSZ. We therefore estimate the potential methane hydrates resources within the Levant Basin at ~100 trillion cubic feet (Tcf) and its carbon content at ~1.5 gigatonnes.

The Leviathan gas field is the largest accumulation so far discovered in the Southern Levant Basin within the turbiditic Tamar Sand Complex. The discovery of this and other fields in the basin was made possible following acquisition of a vast amount of data since 2000. A consensus has been reached that the basin is dominated by Early Mesozoic extensional blocks related to opening of the Neotethys while Miocene folds formed as a result of its closing. Through the study of geophysical data over the Leviathan gas field and its vicinity, it is suggested that most of what we observe today has been formed since the Early Miocene and that the alleged old blocks are actually intrusive bodies. Their structural timing is accurately constrained by well and seismic data but not their composition, as none has yet been penetrated at any borehole. Mud diapirism is currently assumed, as volcanic or magmatic origin is discarded by magnetic data and salt is yet a remote possibility. The tectonic reconstruction suggests that the Levant Basin developed during the Mesozoic and Early Cenozoic as a set of regional highs and lows that were buried since the Early Tertiary until the Early Miocene by thick conforming sequences including potential reservoir rocks such as the gas-bearing turbiditic sands. It was then subject to an extensional tectonic regime associated with diapirs in the southern part of the basin that formed folded structures while rotational blocks developed to the north, offshore Lebanon. The implications of this tectonic setting on petroleum systems are of prime importance; widespread intrusions may have breached old traps, if they existed. On the other hand they formed potential traps such as the proven gas-filled structures and potentially others at depth. Presence of reservoir rocks and the timing of expulsion and migration from deep sources are the main geological risks. [ABSTRACT FROM AUTHOR]

Groupers are important components of coastal ecosystems as well as a valuable resource for fisheries. Their populations are known to be decreasing throughout the world primarily due to over-exploitation. However, even the basic data for an effective management strategy is lacking. Interviews of a representative sample of 113 fishers in Turkey in the northeastern Mediterranean were conducted with specific questions regarding fishing gears, periods and areas as well as best day's catch and the sizes of fishes caught. Fishermen recognized Epinephelus marginatus , E. aeneus , E. costae , Hyporthodus haifensis , Mycteroperca rubra and Polyprion americanus distributed in the area. “Endangered” E. marginatus and “Near Threatened” E. aeneus were the dominant species of the grouper fishery. Based on best days’ catch values and reported lengths of fish caught, the northern coasts of Iskenderun Bay were found to be important for both species. Demersal longliners, spearguns, traps, anglers and demersal trawlers were reported catching groupers in the study area. Artisanal fishermen, especially demersal longliners contributed the most to the grouper fishery. Fishing pressure were subject to seasonal fluctuations, with decreasing reported catches during summer when threatened groupers spawn. Finally, some critical aspects of fishery pressure were related to the removal of juveniles which may lead to reproduction loss. [ABSTRACT FROM AUTHOR]

We present new evidence of deformation features supporting a multiple deformation phase mechanism of the Messinian evaporites, through the interpretation of Pre-Stack Depth Migration (PSDM) seismic data including all intra-salt, base of salt (BS) and top of salt (TS) reflectors. The mechanism presented here involves a syn-depositional deformation event caused by a NW basin tilting during the last stage of the Messinian Salinity Crisis (MSC). This was followed by post-depositional differential sediment loading through radial spreading of the Nile Cone after the MSC. Inside the evaporite sequence, the upper intra-salt units may reside in a brittle domain with predominant thrust faults while the lower units in a ductile deformation domain with folds instead. A NW-flowing channel system is for the first time observed on the TS horizon, suggesting a northwestward basin depocenter during the TS formation. The observed NNW-NNE flow of the water bottom (WB) channels indicates the direction of the current basin depocenter, which suggests a dramatic clockwise shift during post-Messinian. A model of the Messinian evaporite evolution in the Levant Basin during the MSC has been established. The model is based on our observations and the detailed intra-salt interpretation, and is divided into four stages: a) the horizontal deposition of all the intra-salt units excluding the uppermost unit, b) the deposition of the uppermost unit and basin NW tilting occurred coevally or sequentially, c) the TS erosion and the development of NW trending TS channels and d) the deposition of post-Messinian sediments over the evaporite sequence. [ABSTRACT FROM AUTHOR]

The fish assemblages of the Eastern Mediterranean are highly variable owing to the Lessepsian migration. So far, there has been limited discussion about the temporal variation of Lessepsian populations, which may be a key to better understanding the establishment, persistence and spreading dynamics of these species. The objective of this study was, therefore, to develop an understanding of inter-annual variations of Lessepsian fish populations through investigating the effects of climate conditions. For this purpose, we evaluated the data obtained from the seasonal bottom trawl surveys conducted over the course of 12 years, from 2004 to 2015, at the infra-littoral zone of Iskenderun Bay. Our results indicated that Lessepsians constituted 27%, 62% and 85% of total teleost fishes in the number of species (LS-%), biomass (LW-%) and abundance (LN-%), respectively. The linear trends showed that the dominance of Lessepsian fishes increased with annual rates of 1.9 ( p < .01, LS-%), 2.77 ( p < .01, LW-%) and 1.43% ( p < .05, LN-%) per year during the study period. In contrast, seasonal trend decomposition based on GAMMs revealed that the true shape of trends was non-linear. The majority of the new Lessepsians entered the study area after 2009 when warmer conditions prevailed. Those new invaders such as Nemipterus randalli, Pomadasys stridens and Apogon smithi successfully settled in a short time and remarkably altered the composition of fish assemblages after 2010. We found that variations of lessepsian fish assemblages were correlated with the increase of annual minima and average values of sea surface temperature. [ABSTRACT FROM AUTHOR]

Specimens of the penaeid shrimp Penaeus aztecus, a West Atlantic species, were collected off Le Grau du Roi, Gulf of Lion, France, and off the Israeli coast, Levant Basin, Mediterranean Sea. This alien species has been previously recorded off Turkey, Greece, Montenegro and the Tyrrhenian coast of Italy. The species identity was confirmed based on morphological characters and by sequencing 406 nucleotides of the 16S RNA gene and 607 nucleotides of the COI. The 16S rRNA sequences of the specimens collected in Israel, France and Italy were identical, and exhibited three different COI haplotypes. The near-concurrent records from distant locations in the Mediterranean put paid to the premise that P. aztecus was introduced into the Mediterranean Sea in ballast waters. A more prudent proposition is that many of these populations issue from illegal introductions. Potential risks to native biodiversity and economic value are the likely competition with commercially important native prawns, co-introduction of pathogens and parasites, and risk of infecting penaeid populations elsewhere in the Mediterranean Sea with Erythraean alien disease agents previously limited to the Levant. [ABSTRACT FROM AUTHOR]

In the Levant Basin, submarine channels are abundant around the Nile deep-sea fan (NDSF), an area which is also affected by salt tectonics related to the Messinian salt giant. Here we focus on the relationship between submarine channels and obstacles formed by salt tectonics. Initially, we use methods developed for terrestrial morphological analysis and quantify channel sinuosity, width and slope in search for consistent relationships between morphometric parameters and channel response to obstacles. However, this traditional analysis did not yield robust conclusions. Then, we apply two new morphometric parameters suggested here to express the distortion of channels by obstacles: incident angle (α), defined as the acute angle between the regionally influenced channel direction and the strike of the tectonic obstacle and diversion angle (Ω), defined as the angle between the direction of the regional bathymetric slope and the average direction of the channel. These parameters illustrate the influence of the regional-scale basin geometry and the superimposed tectonic-influenced seabed patterns, on channel development. We found hyperbolic relationships between incident angle (α) and diversion angle (Ω) in which channels flowing approximately parallel (α ≈ 0°) to tectonic folds are (obviously) not diverted; channels nearly orthogonal (α ≈ 90°) to obstacles, crosscut them right through and, again, not diverted much. In contrast, channels with a general direction diagonal to the obstacles (α ≈ 40°), are diverted by ten degrees (Ω ≈ 10°). This diversion accumulates along large distances and significantly influences the regional development of channels around the NDSF. Noteworthy, this phenomenon of channel diversion, indirectly deteriorate normal slope-sinuosity relationships known from terrestrial studies. In light of these findings, we suggest that these new parameters can be applied to other basins, where submarine channels interact with seabed obstacles. [ABSTRACT FROM AUTHOR]

The link of the Mediterranean Sea to the Indian and Pacific Oceans was artificially created with the opening of the first Suez Canal in 1897, and the second in 2015, allowing the direct passage of marine organisms into the Eastern Mediterranean Sea. About 307 macroalgae (seaweeds) exist in the Israeli Mediterranean shores. The current study lists marine macroalgae within the Levant basin described after the year 1900, with special focus on species from Israeli shores. We identified 86 species for the whole Levant area regarded as exotic, namely, introduced by artificial vectors derived from human activities, including arrivals via the Suez Canal (Lessepsian invasion). Of those 86 species, 42 are Rhodophyta, 23 are Chlorophyta and 21 are Ochrophyta. Further, about 68% are of Indo-Pacific origin, 20% of Atlantic origin, with 12% of the species of uncertain origin. With precaution, we suggest that about 16% of the marine flora in the Israeli Mediterranean shores are of exotic nature. This survey also indicates that about half of the exotic Ochrophyta are of Atlantic origin, while there are no reports of Chlorophyta of Atlantic origin in the Levant basin. Key aspects when evaluating the exotic nature of marine macroalgae are the trustworthiness of past taxonomic identification and long-term records and description of seaweed collections, both particularly troublesome for the Levant basin. [ABSTRACT FROM AUTHOR]