Crustal Structure of the Levant Basin and Impact on Basin Development and Hydrocarbon Prospectivity
Oscar Fernandez, Nasser Aissaoui, Nuria Antich, Nourdine Ibrihen, Alessandro Roviello, Judith Vila, Andre Vayssaire, and Jean Gerard
Tectonic evolution of the Levant basin is controlled by three main events: 1) opening of the Tethys during the latest Paleozoic to early Mesozoic, with the related rifting along the Levant and northern Africa and formation of oceanic crust; 2) the convergence of Africa and Eurasia during from Late Cretaceous times that leads to the inversion of pre-existing rift features and subduction along the Cyprus Arc; and 3) the Neogene opening of the Red Sea that leads to the, mostly transpressional, reactivation of structures.
The geometry of the rift structure varies significantly from the southern to the northern Levant basin, across a major SW-NE trending crustal lineament that separates extremely thinned continental crust or transitional crust to the north from rifted continental crust to the south. This contrast in rift geometry impacts the structural style and subsequent subsidence. As a consequence, in the northern Levant, broad, basement-involving structures are limited to the basin margins and deformation within the basin is recorded by reduced-wavelength structures that detach within the Tertiary sediments. In the southern Levant, on the other hand, structures are predominantly broader and basement-involving.
The difference in crustal character also means subsidence in the northern basin is greater, both during the post-rift phase (Mesozoic) and during subduction of Levantine crust under the Cyprus Arc (Tertiary). This, in turn, has a significant impact on the expected sediment pathways, deposition and the potential distribution of Tertiary reservoirs. Furthermore, faster subsidence during the early Tertiary in the northern basin led to the deposition of deeper, more distal facies that act as sub-Miocene structural detachment levels during Neogene times, a phenomenon not observed in the southern basin. Finally, greater subsidence in the northern basin also increases the likelihood of thermogenic hydrocarbon generation from Tertiary sediments.
AAPG Search and Discovery Article #90161©2013 AAPG European Regional Conference, Barcelona, Spain, 8-10 April 2013