Time Constrains and the Tectono-Sedimentary Setting of the Permian Sequence in Israel: Insights from Pleshet-1 and David-1 Boreholes, Western Israel

Abstract: Benthic foraminifera, carbonate microfacies identification, and geochemical analysis of the Permian intervals of Pleshet-1 and David-1 boreholes from western Israel,-allowed a determination of their time frame and tectono-sedimentary relationships, further allowing insights about the nature and regional subsurface expression of the Permian. Carbonate horizons within the mixed lithology successions, yielded foraminifera suggesting the Middle/Late Permian transition. The carbonate microfacies and related stable isotopic profiles indicate a change from siliciclastic marginal marine conditions (Saad Fm.) to fully marine platform conditions (Arqov Fm.) in a gradual marine transgression onto a segmented peneplain, and producing sedimentary facies belts striking SW–NE. A comparison of this work with previous work in southern and eastern Israel suggests that the Permian formations in Israel formed NW to SE diachronistically, by marine transgression during the Middle and the Late Permian, with maximum flooding during the Changhsingian. It appears that although not precisely defined, the regional Middle/Late Permian transition happened during a major marine transgression, characterized by a negative to positive stable isotope shift, and by apparently gradual aridization of the hinterland. The regional onset of sedimentation occurred on a marginally superficially downfaulted northwestward peneplain, subdivided tentatively into four segments with shallow half-graben structures. The three eastern segments ceased their differential movements and maintained uniform northwestward subsidence during the late Wuchiapingian–Changhsingian. The most western fourth segment had differential fault activity through the Triassic and the Jurassic, and is proposed to be placed on a transition to a proximal tectonic necking zone.