Sedimentologic and Stratigraphic Evolution of Northern Lebanon Since the Late Cretaceous: Implications on the Levant Margin and Basin
Nicolas Hawie, Remy Deschamps, Fadi Nader, Christian Gorini, Carla Muller, Delphine Desmares, Ahmed Hoteit, Didier Granjeon, and Francois Baudin
This paper aims at presenting an updated review of the northern Lebanese Upper Mesozoic and Cenozoic stratigraphy, allowing to better constrain the hiatuses’ ages as well as to subdivide the poorly dated Senonian (i.e old term used to define the Coniacian to Maastrichtian) rock unit through nannofossil and planktonic foraminifera. The use of well cores and outcrop sections permitted to subdivide for the first time the Chekka type section into four sub-units: (1) Upper Santonian, (2) Lower and (3) Upper Campanian as well as (4) Lower Maastrichtian. The related outer-shelfal facies mark the major drowning of the Upper Cretaceous rudist platform.
The missing Late Lutetian to Late Burdigalian deposits in northern Lebanon seems to be a direct consequence of the major geodynamic events affecting the Levant region (i.e. continued collision of Afro-Arabia with Eurasia) potentially enhanced by major regressional cycles (e.g. Rupelian lowstand). This study attests that the Late Burdigalian- Serravallian units of northern Lebanon have been affected by a pre-existing architecture inherited from the pulsating onshore deformation. Facies barriers have been noted around the Qalhat anticline separating an eastern restricted back reefal setting from a coastal open marine one. The acme of Mount Lebanon’s emergence and exposure is dated back to the Mid-Upper Miocene leading to an important erosion of carbonate materials that were subsequently deposited in paleo-topographic lows. Upper Cretaceous to Cenozoic facies variations, as well as the hiatuses depicted demonstrate that northern Lebanon was in an elevated position compared to the south before the Late Miocene deformation linked with the evolution of the Levant Fracture system.
As no wells have yet been drilled in the Lebanese offshore, this investigation proves to be crucial in trying to assess and predict the depositional environments and associated facies expected for the northern Levant Basin.
AAPG Search and Discovery Article #90161©2013 AAPG European Regional Conference, Barcelona, Spain, 8-10 April 2013