The Essaouira basin is an important onshore hydrocarbon-generating basin in western Morocco. There are seven producing or shut-in oil and gas fields. Six produce from Jurassic and one from Triassic reservoirs.
Basin modeling and geochemical evidence suggest that hydrocarbon generation occurred from at least two source rocks: (1) Jurassic (Oxfordian) shale accumulated within the Neknafa syncline, and (2) deeply buried Carboniferous coals underlying the eastern basin area. The Oxfordian shale was sufficiently buried in western Essaouira to generate voluminous gas and condensate liquids, and to expel them into structurally closed Jurassic reservoirs (Toukimt field) or offset horst-block Triassic reservoirs (Meskala field). Geochemical evidence suggests that the Jurassic-age reservoirs across the eastern Essaouira basin host commingled gases sourced from Jurassic and Carboniferous strata. Coal methane, generated from a deeply buried Carboniferous interval, may have been the main source for the eastern Essaouira basin. Traps developed as structures draping salt domes at junctions of offset transtensive faults.