The Torok Formation is a
geologic formation in the
National Petroleum Reserve in Alaska (NPR-A). It preserves
fossils
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in ...
dating back to the
Cretaceous period.
Geology
The Torok Formation lies 2,000–4,000 feet deeper than the
Nanushuk Formation
The Nanushuk Group or Nanushuk formation is a geologic group in Alaska in westernmost National Petroleum Reserve in Alaska (NPR-A). Oil in these rocks likely was generated beneath Western North Slope and migrated northeastward into NPR-A. It pres ...
. 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 North Slope can refer to:
* Alaska North Slope, a region encompassing the northernmost part of the U.S. state of Alaska
* North Slope Borough, Alaska, a borough in Alaska whose boundaries roughly coincide with that of the region
* North Slope, Tac ...
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.
The Torok Formation was deposited on the floor of the
Alaska North Slope basin
The Alaskan North Slope (ANS) is a foreland basin located on the northern edge of the Brooks Range. The Alaska North Slope is bounded on the north by the Beaufort Sea and runs from the Canadian border to the maritime boundary with Russia in the we ...
.
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.
It came at the same time as
ConocoPhillips
ConocoPhillips Company is an American multinational corporation engaged in hydrocarbon exploration and production. It is based in the Energy Corridor district of Houston, Texas.
The company has operations in 15 countries and has production in ...
discovery of
Willow project
The Willow project is an oil drilling project by ConocoPhillips located on the plain of the North Slope of Alaska in the National Petroleum Reserve in Alaska entirely on wetlands. The project was originally to construct and operate up to five d ...
, which at 300 MMBO is less than a third of the size.
See also
*
List of fossiliferous stratigraphic units in Alaska
*
Paleontology in Alaska
References
*
Cretaceous Alaska
{{Cretaceous-stub