The North Slope Foreland Basin, Alaska
Published:January 01, 1992
The North Slope foreland basin, also called the Colville basin or trough, is a late Mesozoic and Cenozoic basin that spans the entire width of the North Slope of Alaska (Figure 1). It is bounded on the south by the Brooks Range, a thrust-faulted orogenic mountain belt that is an extension of the Rocky Mountains of Canada. The northern boundary of the basin approximately coincides with the north shore of Alaska, the Beaufort Sea, where a rift shoulder that is now a subsurface passive high, the Barrow arch, separates the foreland basin to the south from the Canada basin to the north. To the west, the North Slope basin extends offshore under the Chukchi Sea as far as the northwestward-trending Herald arch and the northward-trending Chukchi platform located along the U.S.-U.S.S.R. boundary (Figure 2). On the far east, the basin narrows; along the Alaska-Canada border, the Brooks Range orogene extends almost to the coastline. Beyond that area and offshore to the east and northeast, the sedimentary fill merges with the Cretaceous and Tertiary passive margin deposits of the Mackenzie delta and Canada basin. As thus defined, the North Slope basin is about 1000 km (600 mi) long and 50 to 350 km (30 to 215 mi) wide, and covers an area of about 240,000 km2 (93,000 mi2).
Because of the hostile arctic environment and the distance from market outlets, hydrocarbon exploration in the North Slope basin occurred much later than that in the foreland basins of the lower 48 states
Figures & Tables
Foreland Basins and Fold Belts
This publication is the fourth in the AAPG Petroleum Basins Series and focuses on the Western Canadian basin and foreland as the type area, with five analog basins in the United States, Iran, and Venezuela.