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The Levant Basin in the Eastern Mediterranean contains a ~3 km-thick, predominantly siliciclastic section of Oligocene-Miocene age, which hosts large hydrocarbon reservoirs (“Tamar Sands Play”). A fundamental question raised with respect to this siliciclastic section concerns its origin and the sedimentary pathways into the deep basin. Here we present an advanced provenance study, including detrital zircon U-Pb-Hf and heavy mineral assemblage investigations, of Oligocene-Miocene siliciclastic sediments retrieved from four boreholes across the Levant Basin. Our investigations reveal a preponderance of Neoproterozoic and older Precambrian zircons with mostly negative εHf values. This U-Pb-Hf pattern indicates that the studied sediments were mainly reworked from Paleozoic-Mesozoic sandstones of Afro-Arabia with variable derivation from the juvenile basement of the Arabian-Nubian Shield. Comparison of the detrital signal in various stratigraphic levels of the Levant Basin shows that Early Oligocene and Early Miocene sand intervals are typified by a large proportion of pre-900 Ma zircons (ca. 50%), by a relatively small proportion of Neoproterozoic zircons with positive εHf values (ca. 25%), and by abundant detrital apatite peloids in the heavy mineral fraction. Resembling Miocene clastic sequences preserved in Israel, these characteristics are taken by us to indicate a dominant provenance in the Arabian side of the Red Sea Rift. On the other hand, Late Oligocene-lowest Early Miocene and Middle-Late Miocene intervals are typified by a mild proportion of pre-900 Ma zircon (ca. 35%) and by a larger proportion of Neoproterozoic zircons with positive εHf values (ca. 35%), they also contain scarce Mesozoic-Cenozoic zircons. These similarities to the Nile Delta sediments are taken by us to indicate a dominant provenance in NE Africa. Overall, our findings suggest that the Levant Basin was fed by varying proportions of sediments derived both from Arabia via the Levant continental margin and from NE Africa via the Nile Delta. While Early Oligocene and Early Miocene sediments, including the main section of the “Tamar Sands”, were chiefly derived from Arabian sources, Late Oligocene-lowest Early Miocene and Middle-Late Miocene sediments mainly sourced from NE Africa. The mere absence of Paleozoic and Mesozoic-aged detrital zircons, abundant in the Eurasian side of the Eastern Mediterranean, suggests that sand sourcing in the overriding plate of the Arabian-Eurasian collision belt did not reach the Levant Basin.

The northern extent of the supercontinent Gondwana in the late Neoproterozoic-Cambrian is not well defined. In most localities the continental margin is covered by thick sedimentary successions, formed following the successive rifting of Tethyan Oceans that episodically detached continental terranes from the edge of the supercontinent. East of the Mediterranean, despite the continental continuity between the Arabian-Nubian-Shield (ANS) and the Tauride block (a Cadomian terrane), the original transition between the two crustal domains is inaccessible and remains obscured. In Israel, investigations of Late Ediacaran, late-stage igneous intrusions of the ANS in the South, together with granulite xenoliths from the lower crust in the North, allow us to probe into the North-Gondwana edge in the late Neoproterozoic and envisage its transition towards the peri-Gondwana Cadomian realm, as well as the evolution of the North Gondwana crust subsequently to the Neoproterozoic. Geochronology and isotopic geochemistry of alkaline intrusions in the Amram massif (southern Israel) as well as doleritic intrusions in the late Neoproterozoic Zenifim Formation (subsurface of south-central Israel) has revealed an igneous and thermal imprint at ca. 550 Ma recorded by the reset of apatite U-Pb ages, together with additional apatite U-Pb dates taken to represent crystallization. Nd and Hf isotopes in apatite, zircon and whole rock also show the ca. 550 Ma intrusions are isotopically distinct from the ANS and resemble Cadomian magmatism in the Taurides. Granulite xenoliths from the lower crust under the lower Galilee (North Israel) contain abundant zircons of distinct U-Pb-Hf properties. These include detrital grains remnant of Neoproterozoic sediment that was subducted and relaminated to the lower crust, late Carboniferous zircons (peaking at 300 Ma) with contrasting εHf(t) signatures, some of which represent syn-Variscan magmatism, and zircons with the age of the host Pliocene basalt. We demonstrate that the Cadomian (ca. 550 Ma) igneous and thermal imprint on the North ANS may have been driven by proto-Tethys subduction that brought about sediment relamination to the North Gondwana lower crust in the latest Neoproterozoic. The late Carboniferous ages recorded in the xenoliths involve both the reworking of depleted ANS basement as well as the relaminated sediment in the means of metamorphism and minor magmatism. Carboniferous thermal disturbance was associated with the formation of continental scale basin and swell architecture across present-day N Africa, Arabia and Iran, and the development of ‘Hercynian unconformities’ in these areas, that were located at the time south of the passive(?) margin of Paleo-Tethys.

Situated between Africa and Eurasia in the eastern Mediterranean, the island of Cyprus has developed on the northern margin of the southern Neotethys by the accretion of three terrains, the Mamonia complex, the Troodos ophiolite, and the Kyrenia terrane. The Kyrenia terrane comprises a tectonic stack of Triassic to Eocene rock units interleaved with basic and acid volcanics and minor metamorphic inliers, alongside an Oligocene-Miocene flysch. Our U-Pb-Hf detrital zircon investigation in the Kyrenia Triassic to Eocene section reveals a large amount of Neoproterozoic zircons (950-600 Ma), alongside Silurian (∼430 Ma), Carboniferous (∼300 Ma), Triassic (∼240 Ma), and Upper Cretaceous (∼85 Ma) zircons. The Precambrian age profile of all three studied units resembles that of Paleozoic sandstones of the Tauride Block, as well as that of Paleozoic and Mesozoic sandstones found across North Africa. It is interpreted as reflecting the reworking of Paleozoic sandstone units from the Taurides or other peri-Gondwanan source. The presence of a substantial proportion of ~300 Ma zircons, as early as in Triassic sediments of the Kyrenia, is of significant interest because Carboniferous magmatism is confined to the Paleotethyan realm which is traced north of the Taurides. Deposition of the Kyrenia sequence closer to a Northern Tethyan province would better fit its detrital zircon signal. The detrital signal of the Kyrenia, indicative for Eurasian terranes north of the Mediterranean, also differs significantly from that of the Mamonia Complex (SW Cyprus) in which only Afro-Arabian sources are distinguished. Thus, in view of its unusual detrital zircon content, the Kyrenia sequence stands out in the Eastern Mediterranean as an exotic rock pile that cannot be straightforwardly correlated with its neighboring geologic environment.