Stratigraphic evolution of the North Levant Platform (Syria) during Aptian to Early Turonian

Abstract

The Levant margin includes the easternmost part of the Eastern Mediterranean in a region where the oceanic (Tethyan) plates and the Arabian, African and Eurasian crustal plates interact. The tectonic events in relation with these plate deformations resulted in the division of the Levant into several provinces; the Southern, the Middle and the Northern. The studied area forms the Northern part of the Levant Platform. The combination of relative sea changes, tectonics, volcanism and local, regional and global environmental perturbations in the North Levant left imprints on the Aptian - Early Turonian carbonate platform configuration and depositional settings. The latter are reconstructed within a nimproved stratigraphic framework, based on field observations, high resolution biostratigraphy, geochemical analysis, detailed microfacies distribution and sequence stratigraphy. The Aptian Early Turonian succession of the North Levant in the South Palmyrides and Coastal Range of Syria represents two different depositional environments of the intra platform rifting basin (Palmyrides) and passive marginal basin (Coastal Range). Deposition was controlled by terrigenous input and/or nutrition resources, syn-depositional volcanic activity, climatic and sea level change which gives the Aptian and the Albian Early Turonian its characteristic features. A high resolution stratigraphic calibration of the Aptian - Early Turonian strata of the Coastal Range and South Palmyrides are based on the integrated identification of benthonic and planktonic foraminifera, in comparison with carbon isotope signals and (subsurface) logs. The abundant larger benthonic foraminifera in all outcrops of both areas allow to subdivide the Aptian - Early Turonian succession into 7 biozones in the Coastal Range and five in the South Palmyrides. Locally abundant planktonic foraminifera allow the subdivision of the latest Aptian - Cenomanian succession into seven biozones in the South Palmyrides, comparing to seven biozones range from the latest Albian to Early Turonian. Carbon isotope fluctuations record significant perturbations that are well comparable with several global changes of the carbon cycle: OAE1c, OAE1d, LCE I-III, MCE, and OAE2. The carbon isotope record is calibrated by high resolution biostratigraphic data, especially during rising sea levels. The comparison of the sequence stratigraphic interpretation with the major depositional systems shows that the depositional systems correspond very well with deepening-up, maximum flooding surfaces (mfs) and shallowing-up cycles that were applied to support the sequence stratigraphic model. Based on high resolution microfacies and gamma ray logs of five wells, the Aptian-Early Turonian succession was subdivided into eleven 3rd order (Syrian) depositional sequences, bounded by major unconformities. Three Aptian sequences of the Coastal Range and the South Palmyrides with mfs K80, K81S, K82S correlate partly with Arabian mfs (v. Buchem et al., 2012); four Albian sequences of the Coastal Range and two of the South Palmyrides with mfs K83S, K100, K110, K120 and five Cenomanian sequences (mfs K121S, K130, K131 S, K140) are defined.