Tingmerkpuk Member of the Ipewik Formation

Unit symbol: Kit
Age range Lower Cretaceous, Valanginian (139.8 to 132.9 Ma)
Lithology: Sedimentary
Group name: Kingak Shale, Shublik Formation, and Karen Creek Sandstone, undivided
Where map data allows, the quartz sandstone in the Ipewik Formation, informally known as the Tingmerkpuk sandstone (see Mull, 2000 and included references), is distinguished here. It is mapped separately because of its importance in potential interpretations of “the tectonic evolution and hydrocarbon potential of the Colville Basin” (Mull, 2000) and because of its apparent northern source and composition, consisting of ~96 percent monocrystalline quartz (Reifenstuhl and others, 1998a)

Source map information

Source map Sable, E.G., and Mangus, M.D. 1984, Geologic map of the west-central Kukpowruk-Nuka Rivers region, northwestern Alaska: U.S. Geological Survey Miscellaneous Field Investigations Map MF-1669, 2 sheets, scale 1:63,360.
Symbol Koq
Unit name Okpikruak Formation, quartzite member
Description Consists of light- to dark-dark gray siliceous, silty quartzitic subgraywacke to orthoquartzite sandstone interbedded with beds of siltstone, variegated shale, and coquinoid sandstone with fine-ribbed Buchia. Sandstone is ripple-marked and thinly crossbedded; clasts are mostly quartz and chert
Lithology Sedimentary

Correlated geologic units

Label Kit
Description Ipewik Formation, Tingmerkpuk sandstone member, northern Alaska, Early Cretaceous, Valanginian
Geologic age Valanginian
Geologic setting Sedimentary, shallow-marine-siliciclastic
Lithology Form Importance
Quartzose-sandstone < Sandstone < Clastic < Sedimentary Bed Major