Alaska Paleontological Database

Sample Detail

Sample:	Sample No. 60AHr72
Locality:	Field No. 60AHr72
Description:	Location determined on Russian Mission 1:250,000 map, 1950 Edition. Coords: 0.6, 10.3, Long. 161^o 55.5', lat. 61^o 35.5'. Near the downstream end of prominent rock bluff on east side Yukon River about 3.5 river miles downstream from village of Ohogamiut. Fossils occur in thin-bedded olive-green tuff or siliceous siltstone interbedded with medium to coarse-grained gray and gray green sandstone.
Location:	Alaska Quadrangle: Russian Mission C-8 Lat.: 61^o35.5 ^' Long.: 161^o55.5 ^'

Reference

Title:	Report on Referred Fossils , 1960 (09/20)

Report by:	Ralph W. Imlay
Referred by:	Joseph M. Hoare


Age:	Jurassic






Comment:	Collection 60AHr72 consists of poorly preserved external molds of belemnites that have long slender guards similar to those of the genus Cylindroteuthis, which occurs fairly commonly in the Jurassic of Alaska. The common Early Cretaceous (Valanginian) belemnite in Alaska is Acroteuthis which has a stout guard and a long deep groove and hence is quite different in appearance from Cylindroteuthis. We have as yet no records of Cretaceous belemnites in Alaska younger than the Valanginian stage, although both Jurassic and Valanginian belemnites have been found reworked into the Upper Cretaceous. A discussion of some reworked occurrences is given on pages 5 and 6 of my report to Authur Grantz dated Nov. 11, 1953 (Shipment A-53-25).