of
Sample: Sample No. 78AYb63
Locality: Field No. 78AYb63
Description: Shelikof Formation. Chignik B-2 quadrangle. Lat. 56o 26 min. 07 sec. N., long. 158o 37 min. 55 sec. W., sec. 30, T. 43 S., R. 59 W., steeply dipping beds on south side of Conglomerate Creek; dark brownish-gray siltstone.
Location: Alaska Quadrangle: Chignik B-2
Township&Range: T43S R59W Section: Sec.30
Lat.: 56o26'07 " Long.: 158o37'55 "
Reference
Title: Report on Referred Fossils ,  1978 (10/03)
The ammonites collected from the upper 350 feet of the 600 feet of the Shelikof Formation exposed near Chignik Bay apparently represent two stratigraphic levels based on comparisons of the taxa present with those found elsewhere on the Alaska Peninsula (See Prof. Paper 836, fig. 6 on page 12). Those collections containing PSEUDOCADOCERAS GREWEINGKI (Pompeckj) have been found elsewhere on the peninsula only in the middle member of the Shelikof Formation. Those containing P. PETELINA (Pompeckj) in association with CADOCERAS COMMA Imlay and C. cf. C. GLABRUM have been found elsewhere on the peninsula only in the highest part of the lower member. Those containing only P. PETELINA could represent either the highest part of the lower member or any part of the middle member. By comparison with the sequence west of Cook Inlet the beds containing PSUEDOCADOCERAS GREWINGKI in association with CADOCERAS COMMA could represent the upper part of the Tonnie Siltstone Member or any part of the overlying Paveloff Siltstone Member. However, the presence of an ammonite resembling C. GLABRUM suggests that the beds are not younger than the Tonnie Siltstone Member.

The age of the upper 365 feet of the Shelikof Formation near Chignik Bay based on comparisons with the ammonites found elsewhere in southern Alaska (See Prof. Paper 836, fig. 8 on p. 14) is mostly of early Callovian age but could be partly of early middle Callovian age. Apparently the lowest ammonites collected near Chignik Bay are younger than the INISKINITES bearing beds west of Cook Inlet, which beds are now assigned to the late Bathonian on the basis of recent studies in Canada and Oregon.

Report by: Ralph W. Imlay
Referred by: Robert L. Detterman
Age: Callovian (early Callovian)
Formation: Shelikof Formation
Occurrence(s)
No. Group Name Qty Notes
1 Ammonoids Pseudocadoceras cf. P. petelini (Pompeckj)