Stratigraphic Trap Potential in the Middle East – Examples from the Mesozoic

Abstract The Mesozoic stratigraphy of the Middle East is endowed with multiple world-class, economically significant petroleum systems. Since the first discovery of a major oilfield in an anticline structure in 1908 (Masjed-e-Suleyman, Iran), exploration and production in the Middle East has been largely focussed on relatively low-risk, large structural traps. However, across the Arabian Plate, unexplored structural traps at similar scales are becoming scarce. Therefore, in this mature petroleum province, attention must now focus on identifying the presence of subtle stratigraphic traps, especially within the hydrocarbon-rich Mesozoic stratigraphy. In order to locate and evaluate subtle stratigraphic traps, we have applied sequence stratigraphic principles across the Mesozoic strata of the Arabian Plate. This approach provides a regional, robust age-based framework which reduces lithostratigraphic uncertainty across international boundaries and offers predictive capabilities in the identification and extent of stratigraphic plays. Herein, we focus on three intervals of Mesozoic stratigraphy, namely Triassic, Middle-Late Jurassic and middle Cretaceous strata, in which regional sequence stratigraphic based correlations have identified stratigraphic trap potential. Each of these stratigraphic intervals are associated with the following stratigraphic traps:Triassic: Sub-crop traps associated with a base Jurassic regional unconformity and intra-Triassic unconformities. Onlap geometries associated with differential topography on the Arabian Plate.Middle-Late Jurassic: Pure stratigraphic trap geometries associated with basin margin progradation and pinch-out plays either side of the Rimthan Arch related to late Oxfordian/early Kimmeridgian sea-level fall.Middle Cretaceous: Sub-crop potential beneath the regional mid-Turonian unconformity, basin margin progradation and stratigraphic pinch-out geometries associated with onlap onto basin margins. This regional sequence stratigraphic approach highlights the remaining exploration and production opportunities within these hydrocarbon-rich stratigraphic intervals.