This report covers 5 collections, comprising some 60-odd specimens, from the unnamed sandstone-shale formation. Excepting for the lowest collection, all contain abundant small rugose corals of types found elsewhere in the uppermost Kayak shale and lower Wachsmuth limestone. They are of early Mississippian age, possibly an early Osage equivalent.

Collection 128 from the nonmarine portion of this unit contains only a crush carbonized plant fragment which is indeterminate.

Collection 59ACu30f, not from the measured section, ressembles 116f and likely represents about that level in the formation.

Coarse clastic rocks and nonmarine facies appear higher in the sequence in the Cape Thompson area than in the Brooks Range to the east. In the central Brooks Range, the nonmarine facies is probably all of late Devonian age while near Cape Thompson it may well include Kinderhook equivalents as well.

This clastic phase has been assigned to the Noatak sandstone (restricted) and the Utukok formation in the western DeLong Mountains. The boundary between these two units is at the breakover to marine deposition. I would say this some 300 to 400 hundred feet below the base of Ml₁ in the measured section. In a section that I measured in 1951, near or possibly at the same place as your measured section, I found plant fragments in carbonaceous sandstone beds up to about 800 ft. below the base of Ml₁. Nearly 500 ft. of shale with ironstone nodules separate the plant-bearing beds from the lowest marine fossils.

I would suggest that the lower 1500 feet of so of the sandstone-shale unit is a Noatak sandstone equivalent and that the upper 300 or so feet, plus unit Ml₁ is a Utukok formation equivalent.

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Brief statement of problem and remarks (from collector):
Attempt defininte age determination. Attempt definite formation assignment- Kayak, Kanayut, Noatak??

Field notebook reference: Campbell, Chariot, 1959, Notebook #2, p. 13, 14, 29, 31.