Torok Formation

Last updated
Torok Formation
Stratigraphic range: Cretaceous
Type Formation
Location
Region Alaska
Country United States

The Torok Formation is a geologic formation in the National Petroleum Reserve in Alaska (NPR-A). It preserves fossils dating back to the Cretaceous period.

Contents

Geology

The Torok Formation lies 2,000–4,000 feet deeper than the Nanushuk Formation. They form a huge wedge of sediment deposited in a deep water basin and stretch from north of the Brooks Range beneath the Alaska North Slope to the adjacent offshore. It contains reservoirs in turbidite sandstone and is very porous. The USGS found large-scale folds and faults in the South of the formation and evidence, that the rocks have been heated to temperatures at which oil is converted to natural gas. [1]

The Torok Formation was deposited on the floor of the Alaska North Slope basin. [1]

History of oil exploration

In 2016, oil discovery in the deeper Torok Formation of more than 1,000 MMBO was announced at Smith Bay, less than 1 mile offshore from the NPR-A. [1] It came at the same time as ConocoPhillips discovery of Willow project, which at 300 MMBO is less than a third of the size. [1]

See also

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References

  1. 1 2 3 4 David W. Houseknecht, Richard O. Lease, Christopher J. Schenk, Tracey J. Mercier, William A. Rouse, Palma J. Botterell, Katherine J. Whidden, Christopher P. Garrity, Kristen A. Lewis, Samuel J. Heller, William H. Craddock, Timothy R. Klett, Phuong A. Le, Rebecca A. Smith, Marilyn E. Tennyson, Stephanie B. Gaswirth, Cheryl A. Woodall, Michael E. Brownfield, Heidi M. Leathers-Miller, Thomas M. Finn (2017). "Assessment of undiscovered oil and gas resources in the Cretaceous Nanushuk and Torok Formations, Alaska North Slope, and summary of resource potential of the National Petroleum Reserve in Alaska, 2017". U.S. Geological Survey. doi: 10.3133/fs20173088 .{{cite journal}}: CS1 maint: multiple names: authors list (link)