Pg. 51-55, pls. Snug Harbor Siltstone Member of Naknek Formation. Replaces Kirschner and Minard's (1948) siltstone member of Naknek Formation. Dominantly massive to thin-bedded dark-gray to black siltstone. Calcareous thin-bedded gray sandstone is minor constituent of section. Thickness 720 to 860 feet with thickest part at type section. Underlies Chisik Conglomerate Member; overlies Pomeroy Arkose Member (both of Naknek Formation). Age is at least as old as late Oxfordian and may be as young as middle Kimmeridgian (Late Jurassic). Report includes fossil lists and localities.
Type section: exposed in sea cliffs of Snug Harbor, along southwest shore of Chisik Island. Section starts about 1,000 ft north of extreme southern tip of the island and continues north along the shore for 3,200 ft in strata that dip 19 to 20 deg. SE, Iniskin-Tuxedni region, southwestern AK. A small indentation of the coastline has been known for many years as Snug Harbor.

Source: US geologic names lexicon (USGS Bull. 1350, p. 706); supplemental information from GNU records (USGS DDS-6; Menlo GNULEX).

Snug Harbor Siltstone Member of Naknek Formation. Unit geographically extended into report area (Sutwik Island D-5 quadrangle, scale 1:63,360). Reference section designated along Northeast Creek (about 1 km north of type section), on top of and down southeast face of flat-topped ridge, in sec. 27, T. 37 S., R. 51 W. Thickness is 637 m. Age is Late Jurassic.

Source: GNU records (USGS DDS-6; Menlo GNULEX).