Tectono-stratigraphic evolution of the Late Cretaceous-Eocene of Jordan and implications for the Arabian Plate convergent margin phase

Abstract

The Late Cretaceous-Eocene geodynamic evolution of Jordan is presented, combining, for the first-time, outcrop and subsurface data in this poorly known, yet important part of the Arabian Plate. A new age model developed for outcrop sections, integrating biostratigraphy, C/O and Sr isotopes, together with seismic and well log data significantly improves the timing of the structural events in Jordan and shows their potential relationship to Arabian Plate scale deformation events.

The late Albian-early Turonian displays a gradual north-northwestward thickening trend across Jordan during a phase of tectonic quiescence, whereas in the overlying late Turonian-early Campanian there is ample evidence for extensional/transtensional tectonic activity, with an acme during the early Campanian, expressed in the development of the northwest-trending Azraq-Hamza Graben in central-east Jordan. This graben, with an offset of c. 1800 m, extends southeastwards to the Wadi Sirhan Graben in Saudi Arabia and northwestwards to the Levant Basin. The subsequent late Campanian-Eocene succession records reduced tectonic subsidence within the graben during a sag phase and marks a return to regional stability.

The Azraq-Hamza Graben is proven to be time-equivalent to the similarly oriented extensional events in Syria (Euphrates Graben) and Iraq (Sinjar Graben) and is coeval with the compressional structures of the foreland basins in Oman and Iran. This study contributes, to the large-scale tectonic evaluation of the African-Arabian plate deformation and evolution during the Late Cretaceous obduction and subduction phases, which played a critical role in the shaping of the petroleum systems and phosphorite sedimentation of the region.