ABSTRACT The Minjur Formation crops out along the eastern rim of the Arabian shield and consists of alternating sandstone and shales with minor carbonates. Informally subdivided into lower and upper units, the Minjur Formation records depositional environments ranging from alluvial to marginal marine with tidally influenced channels. The stacking patterns reflect delta or shoreline progradation and retrogradation, recording an overall coarsening upward character. In outcrop, the Minjur Formation was dated as Norian by conodonts near the base. In the subsurface, palynology has established a fourfold biostratigraphic subdivision extending from latest Carnian–early Norian to latest Rhaetian–Pliensbachian (Triassic–Early Jurassic). This study improves the understanding of Minjur stratigraphy and presents a depositional model based on surface–subsurface correlation. Subsequent to a period of subaerial exposure in the west, transgression in the early middle Norian was marked by marginal marine environments, with peak marine influence in the mid–late Norian and corresponding to the maximum flooding interval Tr80. This was followed by development of a gently inclined alluvial or coastal plain. An intra-Rhaetian hiatus separates the Lower Minjur Formation from the Upper Minjur Formation (base of TSS AP7[?]), and a variety of depositional environments are represented, including alluvial fans proximally, grading to fluvial to coastal plain and shallow marine environments distally.

Abstract Basin-scale stratigraphic correlation is the fundamental base for successful reservoir exploration, and especially when dealing with cross-border areas. Differences in lithostratigraphic and chronostratigraphic nomenclature between sub-basins and countries often result in problematic estimations of reservoir geometries and potential. This study combines available biostratigraphic, biofaunal and lithofacies data, together with sequence-stratigraphical correlations of the Lower Jurassic from the Central European Basin (CEB), to propose a genetic-based framework of transgressive and regressive depositional units. The determination of four major biofacies environments, composed of (I) polyhaline open-marine/offshore environments, (II) upper mesohaline marine–brackish environments, (III) lower mesohaline brackish environments and (IV) low oligohaline to freshwater continental environments comprising very rare marine phytoplankton and terrestrial spores and pollens, were translated into 12 biofacies reconstructions of ammonite (sub-) chronozone levels. Variations of biofacies reconstructions in time and space were supplemented by biostratigraphically constrained large-scale progradational and retrogradational sedimentary architecture. Retrogradation is accompanied by increasing polyhaline environments and pinpoint basinwide third-order flooding events, whereas progradation is accompanied by decreasing polyhaline environments pointing to third-order regressions. The outcomes of this study support exploration of Lower Jurassic deep geothermal reservoirs or CO 2 storage sites in the eastern CEB (especially Germany and Poland). Supplementary material: A list of all documented Liassic ammonites known from the eastern European shelf area (Denmark, The Netherlands, Sweden, Germany, Poland; wells and outcrops) is available at https://doi.org/10.6084/m9.figshare.c.3923467