Geology
Oil, condensate and gas are produced from the Triassic, Ivishak sandstone. This reservoir was deposited as a complex amalgamation of fan deltas and alluvial fans. The oil is trapped in the Sadlerochit formation, a gravel and sandstone structure nearly 9,000 feet (2,700 m) under the surface. During the field’s early life the oilbearing sandstone in some locations was 600 feet (180 m) thick. Today, the oil bearing zone's average thickness is about 60 feet (18 m).
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