Intricately intruded areas of volcanic graywacke and mudstone

Unit symbol: TKis
Age range Tertiary or Upper Cretaceous (113 to 61.6 Ma)
Lithology: Sedimentary
Group name: Nonmarine to shelf sedimentary rocks
Unit is mapped in areas where numerous small hypabyssal bodies of rhyolite and dacite intrude the Ksd unit. Igneous complexes are composed of small, closely-spaced rhyolite, dacite, andesite, granite, granodiorite, tonalite, and monzonite porphyry bodies. Intrusive bodies are too small and too numerous to be mapped separately. Sedimentary host rocks are altered to erosion-resistant hornfels. A felsic hypabyssal body belonging to the complex in the southwestern part of Unalakleet quadrangle yielded a single K/Ar isotopic cooling age of 68.8±3 Ma (Patton and Moll-Stalcup, 1996)

Source map information

Source map Patton, W.W., Jr., and Moll-Stalcup, E.J., 1996, Geologic map of the Unalakleet quadrangle, west-central Alaska: U.S. Geological Survey Miscellaneous Investigations Series Map I-2559, 39 p., 1 sheet, scale 1:250,000.
Symbol TKrs
Unit name Rhyolite and dacite, and sandstone, shale, and conglomerate deltaic deposits
Description Hypabyssal rhyolite and dacite (Early Tertiary and Late Cretaceous) that are too small and too numerous to be mapped separately at this map scale. Sedimentary host of thermally altered sandstone, shale, and conglomerate
Lithology Sedimentary

Correlated geologic units

Label Ksi
Description Rhyolite and dacite, and sandstone, shale, and conglomerate deltaic deposits and intricately intruded areas of volcanic graywacke and mudstone, late Early Cretaceous (Albian)
Geologic age Albian to Danian
Geologic setting Sedimentary, deltaic-and-nearshore
Lithology Form Importance
Hypabyssal-dacite < Felsic-hypabyssal < Hypabyssal < Igneous Dike or sill Major
Hypabyssal-rhyolite < Felsic-hypabyssal < Hypabyssal < Igneous Dike or sill Major