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Several oil shows have been reported from offshore and onshore wells of the Levant Basin, which promoted research and exploration as indicators for potential economic discoveries in the yet unpenetrated Mesozoic interval of the basin. In most cases, no definitive source to oil correlation has been established, advocating the need for the fingerprinting of regional source rocks to compare their organic geochemical signatures to those of oils. A summary of known properties of oils sampled from different wells in the region raised several questions regarding source–oil and oil–oil correlation, maturity, and source of the organic matter. In this part of the project we examined the Cretaceous section in the region by conducting a sedimentological and organic geochemical investigation of organic-rich intervals from ODP well material and onshore wells in the Levant region. We show that organic-rich Upper Cretaceous deposits, Turonian OAE2, and lowermost Cretaceous Barremian organic-rich deposits, should be considered as viable candidates for sourcing hydrocarbon formation in the deep basin, where they might have matured. more...

Oil shows from wells in the Levant Basin and Egypt are suggestive of potential economic discoveries within unpenetrated Mesozoic reservoirs in the Eastern Mediterranean. Analysis of some of these oils indicate a non-marine source of mixed deltaic-terrestrial or lacustrine origin for the organic matter. Data from Barremian-Aptian sediments from the MNUPH-1 core in northern Israel opens a window on potential importance of terrestrial-sourced kerogen deposited in source rocks in a marine depositional environment. Core analyses of the Barremian Nabi Sa'id Fm. demonstrate the occurrence of a gas-prone immature source rock of >77 m gross thickness averaging 4.6% TOC, peaking at 37% TOC. Rock-Eval pyrolysis, biomarker n-alkane, sterane, and tricyclic terpane indices, atomic C/N ratios, and δ13Corg ranges indicate mixed terrestrial-marine organic source rocks for the Barremian, while higher up, the Aptian Hidra Fm. contains source rocks with organic matter derived dominantly from carbohydrate-rich land plants. The interval at MNUPH-1 includes abundant evidence for off-shelf mass transport of terrestrial and proximal marine sediments into the deep marine basin. These features are used to explain the anomaly of a terrestrial source for organic matter in this setting. Mass transport and consequent mixing of distal marine, proximal marine and land-derived sediment is, in fact, the norm at the foot of continental slopes globally. The dominantly type III source rocks described here would be unlikely to expel oil but might produce thermogenic gas. Thermogenic gas identified in similar marine settings might wrongly be interpreted as having been generated from marine organic matter, misleadingly indicative of a prospective oil source. When prospecting for deep-rooted hydrocarbon accumulations in offshore marine settings, an alternative system dominated by basinward sediment transport of gas-prone ‘terrestrial’ source rocks into strategically-positioned toe-of-slope marine settings, is supported here, and could well be producing gas in the Levant Basin. more...