Mesozoic Petroleum Systems in the Southeastern Mediterranean Continental Margin

By

Michael A. Gardosh¹, Akiva Flexer², Paul Weimer³

(1) The Geophysical Institute of Israel, Lod, Israel (2) Tel Aviv University, Tel Aviv, Israel (3) University of Colorado, Boulder, Boulder, CO

 Commercial accumulations of oil and gas and various hydrocarbon shows were found in the Mesozoic strata at the southeastern Mediterranean area. A subsurface, sequence stratigraphic study and thermal maturity modeling allow the description of several petroleum systems.

The southeastern Mediterranean continental margin evolved from an Early Mesozoic rift system that developed on the edge of the Arabian platform, near the present-day coastline of Israel. The post-rift, shelf to basin profile is composed of six, second-order Jurassic and Cretaceous composite depositional sequences. Highstand systems tracts are various types of aggrading and backstepping carbonate platforms. Lowstand systems tracts are siliciclastic and carbonate deepwater turbidite complexes. Mesozoic source rocks are found in both depositional settings.

Oil production from the onshore, Helez and Ashdod fields is associated with a Middle Jurassic petroleum system. Thermally mature, organic-rich facies is identified in wells at the distal part of Middle Jurassic, backstepping carbonate platforms, near the present-day coastline.

Hydrocarbon shows in several near-offshore wells are associated with two potential petroleum systems: over-mature Triassic source rocks, estimated to be found within Early Mesozoic grabens; and mature, Middle-Upper Jurassic source rocks identified in wells within deepwater turbidite complexes. Thermally mature Senonian, deepwater carbonate strata may compose a third petroleum system in the far offshore. The offshore, Mesozoic petroleum systems are not sufficiently tested by drilling.