Pg. 492. Portneuf limestone of Thaynes group. Top formation of Thaynes group in Fort Hall Indian Reservation, southeastern Idaho. Thickness 1,500+/- feet. Overlies Fort Hall formation. [Age is Early Triassic.]

Source: US geologic names lexicon (USGS Bull. 896, p. 1710-1711).

Pg. 32, 38. Portneuf limestone of Thaynes group. Siliceous cherty gray to yellowish limestone in massive beds; rounded elongated nodules and streaks of chert. [Fossils (echinoids, bryozoans, crinoids, pelecypods, scaphopods, gastropods) identified by G.H. Girty, USGS, see p. 39-40.] Silicified fossils, including SPIRIFERINA n. sp.(?), TEREBRATULA SEMISIMPLEX, and other terebratuloids, and MYAPHORIA LINEATA(?), project from the weathered surfaces. Thickness 1,500+/- feet. Top formation of Thaynes group in Fort Hall Indian Reservation. Underlies Ankareh [now called Timothy] sandstone and overlies Fort Hall formation. Age is Early Triassic.
Named from Portneauf River, at head of which it is well exposed, [in T. 4 S., R. 38 E., Yandell Springs 15-min quadrangle], Bingham Co., Fort Hall Indian Reservation, southeastern ID.

Source: Publication; US geologic names lexicon (USGS Bull. 896, p. 1710-1711).

Pg. 17, 31-33, pl. 1. Portneuf limestone of Thaynes group. Unconformably underlies Timothy formation where mapped in Ammon and Paradise Valley quadrangles. In Lanes Creek, Freedom, and Montpelier quadrangles farther east and southeast, the limestone contains a well-developed red-bed unit, which consists of interbedded red sandstones and shales and ranges from 200 to 1,000 feet in thickness. [Age is Early Triassic.]

Source: US geologic names lexicon (USGS Bull. 1200, p. 3108).

Pg. H-173, fig. 18. Portneuf limestone member of Thaynes formation. Described as member of Thaynes formation. Underlies Timothy sandstone member. [Age is Early Triassic.]

Source: US geologic names lexicon (USGS Bull. 1200, p. 3108).