Stratigraphy and structure of the area of the upper Meade River, Alaska

Abstract

The stratigraphic evidence in the upper Meade River area includes zones B to D of the Nanushuk group (Cretaceous). Zones B and C are not differentiated in mapping and description. South of the Meade River 2,100 feet of zones B-C and 1,500 feet of zone D are exposed. North of the fault zone along the Meade River, the only rocks present, estimated not over 1,000 feet thick, are zone D beds which may be at least in part younger than the zone D rocks south of the Meade River. Sands which barely meet the minimum requirements for potential reservoir beds are present in both zones. South of the Meade River the Kigalik anticline and the Falcon Creek anticline, both sharp-crested folds, trend east. The intervening synclines are broad with low dips on the flanks. Along the Meade River the major structure is a zone of reverse faults, about three-fourths of a mile wide, which brings rocks of zones B-C on the south opposite rocks of zone D on the north. Minimum displacement in this zone is 1,000 feet at longitude 157° 50'W. and 300 feet near the gas-seep lake. North of the fault zone, the Meade River anticline is a rather low fold, so poorly exposed that closure cannot be detected by surface geologic methods.