R. Burwood, 1984. "Carbonate Source Rocks for Six Million Barrels of Oil per Day—Zagros Fold Belt, Southwestern Iran", Petroleum Geochemistry and Source Rock Potential of Carbonate Rocks, James G. Palacas
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The giant fields of the Zagros fold belt of southwestern Iran fall within the greater context of the Arabian-Iraq-Persian basin and contain cumulative recoverable reserves estimated at 87 billion barrels of oil and 514 trillion cubic feet of gas.
The regional geology of the area comprises a wedge of Paleozoic to Holocene sediments, 10–15 km (6–9 mi) or more in thickness, supported on a mobile Eocambrian salt economic basement. Forming a classic carbonate–evaporite sequence, the succession contains prolific source-reservoir combinations and effective seals of integrity. Located on the eastern subducting boundary of the Arabian plate, hydrocarbon generation has been largely controlled by the Neogene Zagros orogenic event. A number of potential source sequences have been recognized. With one exception, all are typically of an organic-rich, argillaceous, lime-mudstone litho-textural type.
Most of the giant oil accumulations in Asmari (Oligocene-Miocene) and Bangestan Group (Upper Cretaceous) reservoirs have a common provenance in the Kazhdumi Formation of Early Cretaceous (Albian) age. The Pabdeh (Paleogene), lower Garau–Gadvan (Lower Cretaceous, Neocomian), and Sargelu (Middle Jurassic) formations contribute less to overall reserves, having been the source for selected subordinate Asmari, Bangestan, and Khami Group (Upper Jurassic-Lower Cretaceous) reservoirs only. Gas in Permian-Triassic reservoirs has a provenance in Ordovician-Silurian siliciclastics.