A detailed study of foraminiferal populations was carried out at three contaminated sitei along the Mediterrarean coast oftrsraei. The unpolluted coast ofNitzanim provided the first natural base line to be determined for the regiou" A total of 158 species of benthic foraminifera from 36 families ryere idenrified along the shallow (6_50 m) parts of the Mediieranean coast of Israel. Anmonia tepida (Cushman), Porosononion subgtanosus meditenanicus Yaako, and'frtbcuiina maiani Schlumberger were the dominant species everlrwhere, rvhereas tlie accessorv soecies varied. A,t Palmahim (domestic sewage) the species diversity 1nd population densify rilas greatest. Here the largest forasriniferal test sizes and the highest percentagi of a gglutircated foraminifera'rere fou;d. h contrast, the lowest species diversiry and population densify occurred near the Hadera power station, where coal was the major source of pollution in the sediment. Part of Haifa Ba;v is currently being contaminated by a variefy of heary metals. In the contaminated site the foraminiferal tests were smaller, often stunted and fre. quently pyritized. A.bberant tests was another more noticatrie response" At least 16 species exhibited abnormal tests. 'Ihe_degree of deformation ranged from mild to exfreme. Benthic foraminifera have been demonstrated to be sensitive in situ monitors or coastal pollution.

A comprehensive study of the Levant region, using geophysical, well and surface data, has elucidated the tectonic regime which preceded the Late Cretaceous tectonic inversion in the Levant region. A tectonic mosaic existed in the study area during the Paleozoic and Mesozoic, and was made up of NE‐trending grabens (e.g. the Pleshet, Judea and Galilee grabens) and their neighbouring horsts, and a number of NW‐trending blocks. These tectonic elements were bounded by regional faults. The grabens were formed in three known phases: pre‐Upper Permian: Early to Middle Triassic; and Early to Middle Jurassic. Formation of each graben resulted in a depositional sag basin centered above the graben and extending beyond its boundaries. Two types of inversion were active—inversion of regional tilts, and inversion of vertical tectonic movements. Examples of regional tilts are the SE landward Middle Triassic Anisian sedimentary wedge. and the NW basinward wedge of the Early Cretaceous (Berriasian to middle Aptian) sequence. A vertical inversion occurred in the Late Cretaceous. The Paleozoic‐Mesozoic grabens became raised blocks, whereas the horsts turned into depressed areas, in which synclinal sediments, rich in organic matter, accumulated in asymmetrical fault‐fold sag basins. These events occurred as a result of intraplate stresses, and are related to major global orogenies. The grabens, the sag basins, and also the argillaceous parts of the basinward sedimentary wedges, are considered to be sites of hydrocarbon generation. Commercial and sub‐commercial production, as well as abundant oil and gas shows, confirm the presence of source rocks. Traps of various forms are widely available; in the horsts, in the grabens, in the sedimentary wedges, and in the sedimentary sag basins.

The nature and tectonic setting of the Eastern Mediterranean Basin are analyzedfrom geological and geophysical points of view. Palaeozoic and Mesozoic stratigraphy and palaeo-biogeography suggest that epicontinental Africa, Apulia and Arabia were united almost continuousl-y during the entire Pharterozoic eon, prior to and a f e r the Early Triassic opening of the Mesozoic Tethys. The allochthonous ophiolite-bearing terranes. that were thrust over the edges of the Gondwanan plate, fit well within a palinspastic model of CI single Tethvs ocean. north of the African-Apulian-Arabian palaeo-edge.Seismic reflection and refraction studies, together with magnetic and gravinietric measurements of the present Eastern Mediterranean Levantine crust. have revealed a sedimentary succession 13-14 kin thick, which pt-esumably includes Palaeozoic -Early Meso,-oic struta oiyerlying crust 8 -12 km thick.Geological andgeophysical re-evaluation suggests that the enormously thick sedimentav succession of the Levantine Basin covers a thinned crust of continental origin. The latter consists of Panafrican terranes, possibly including Infracambrian ocean-crust relics. Its "oceanic "-like nature is presumably due to subcrustal thermal erosion. The possible existence of a western palaeo-high oflshore the Levant Coast calls for reassessment of hydrocarbon exploration in the Eastern Mediterranecin. The previouslv proposed "hinge belt" along the Levant Coast may merely represent the transition from the eastern platform to a graben that separates the eastern (onshore) from the w-estern (ofisshore) highs.The passive extensional regime of the Gondwanan Eastern Mediterranean plate during most of the Phanerozoic eon ended with h t e Cretuceous -Palaeogene Alpine compression (f its margins, and the activation of the on-and offshore Levantinid Syrian Arc fold svstern.

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Element ratios and water stable isotopes reveal the presence of only two independent deep brines in the Kinnarot Basin, Israel: the evaporite dissolution brine of Zemah‐1 and the inferred Ha’on mother brine (HMB) with low and high Br/Cl ratios, respectively. HMB is considered to be a representative of the Late Pliocene evaporated Sedom Sea. The freshwater‐diluted evaporation brine emerges as Ha’on brine on the eastern shore of Lake Tiberias and is also identified in the pore water of lake sediments. HMB is converted into Tiberias mother brine (TMB) by dolomitization of limestones and alteration of abundant volcanic rocks occurring along the western side of the lake. The Ha’on and Tiberias brines, both characterized by high δD and δ18O values, are similar in Na/Cl and Br/Cl ratios but are dissimilar in Br/K ratios because these brines were subjected to different degrees of interactions with rocks and sediments. Excepting the brine from KIN 8, all brines from the Tabigha area including the nearby off‐shore Barbutim brine are related to the TMB. The brine KIN 8 and all brines from the Fuliya and Hammat Gader areas are related to the HMB. The brine encountered in wildcat borehole Zemah‐1 is generated by halite‐anhydrite/gypsum dissolution and is independent from the HMB system.

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