ABSTRACT
The history of structural growth of the Harmaliyah oil field in eastern Saudi Arabia was studied by means of a series of paleostructural maps to determine if early entrapment of hydrocarbons played an important role in preserving the high porosity of the Kimmeridgian (Upper Jurassic) Arab D reservoir. The Arab D has been affected by shallow or preburial diagenesis—a common feature in Arabian Upper Jurassic calcarenitic reservoirs. Closure forming the structural trap in the Arab D at Harmaliyah oil field developed principally during the late Turonian (Late Cretaceous). During Kimmeridgian (Late Jurassic)–early Turonian (Late Cretaceous) time, shallow or preburial diagenesis of the calcarenitic Arab D reservoir rocks seems to have played a major part in preservation of porosity before the porosity was filled with hydrocarbons.
