Sample Detail of
Sample: Sample No. 51AHa9 -- USGS No. Mesozoic loc. 22721
Locality: Field No. 51AHa9
Description: About half a mile below head of a tributary of Bear Creek which joins Bear Creek at a point 2.53 miles from Tuxedni Bay. (description from E&R report of Imlay dated Dec. 20, 1951; Shipment AF-51-42)[Transmittal sheet of Hartsock, dated Nov. 30, 1951 provides further details: "One hundred yards upstream from traverse point 64H on Bear Creek, south side of Tuxedni Bay, about 1/2 mile below head of stream. Ammonite collected in siltstone believed to belong to Bowser formation."][Shown as locality 66 of Detterman and Hartsock, 1966 - Note by R.B. Blodgett: digitization of this point gives approx. lat. 60o 05'57" N., 152o 45'13" W.][Imlay, 1964, p. B23 provides following description: "J.K. Hartsock, 1951. Tuxedni Bay area. On tributary of Bear Creek, 3.56 miles S. 38o W. of mouth of Bear Creek. Fitz Creek Siltstone, 150 ft above base."]
Location: Alaska Quadrangle: Kenai A-8
Lat.: 60o05'57 " Long.: 152o45'13 "
Reference
Title: Report on Referred Fossils ,  1951 (12/20)
The only fossil of stratigraphic value in the three lots from the Difficult member of the Tuxedni formation is an ammonite mold in lot 51AHa6. A clay squeeze of this ammonite compares closely with the adult whorls of Erycites from the basal beds of the Kialagvik formation on Wide Bay. You may recall that Don Miller and I found Erycites associated with Tmetoceras and Pseudolioceras at localities 48 AI 77 and 78 at a spot about 2.6 miles N. 77 W. of Fossil Point. This occurrence is about 350 feet above the highest lava beds and slightly lower stratigraphically than your lot 51AHa6. In Europe Tmetoceras characterizes the basal part of the Bajocian stage. The other genera occur in both the lower part of the Bajocian and the upper part of the Toarcian. From these occurrences it is evident that the thick lava sequence on Tuxedni Bay occupies the stratigraphic position of the Lower Jurassic.

The Gaikema member is represented certainly by lots 51AHa11a, b, c as shown by the presence of the ammonities Emileia, Lissoceras, and Sonninia. The same species were obtained on the south shore of Tuxedni Bay in unit 33 of the section measured by Stanton and Martin (see U.S.G.S. Bull. 776, p. 142) as shown by specimens in lots 3009 and 21263.

The Fitz Creek member is represented by lots 51AHa9 and 10 as shown by the presence of species of Stemmatoceras and Oppelia identical with species obtained on the south shore of Tuxedni Bay in unit 19 of the section measured by Stanton and Martin. Grantz found the same species of Stemmatoceras in his lot 51AGz136, which is a short distance northeast of your localities.

The correlations of these members have been discussed in previous memoranda and are shown by charts in your possession.
Report by: Ralph W. Imlay
Referred by: John K. Hartsock
Age: No Data (no definitive age provided in report)
Formation: Fitz Creek Siltstone (Fitz Creek member of the Tuxedni formation)
Comment:Fossils from the Fitz Creek member

The Fitz Creek member is represented by lots 51AHa9 and 10 as shown by the presence of species of Stemmatoceras and Oppelia identical with species obtained on the south shore of Tuxedni Bay in unit 19 of the section measured by Stanton and Martin. Grantz found the same species of Stemmatoceras in his lot 51AGz136, which is a short distance northeast of your localities.

Occurrence(s)
No. Group Name Qty Notes
1 Ammonoids Oppelia cf. O. subradiata (Sowerby)

Title: Geology of the Iniskin-Tuxedni Region, Alaska ,  1966
Report by: Robert L. Detterman , John K. Hartsock
Age: Bajocian (middle Bajocian)
Formation: Fitz Creek Siltstone
Comment:Geographic location: Bear Creek
Map reference (pl. 3): 66
Stratigraphic position below top of formation (ft): 150
all above data from Table 6, p. 33
Occurrence(s)
No. Group Name Qty Notes
1 Ammonoids Oppelia stantoni Imlay

Title: Middle Bajocian ammonites from the Cook Inlet region, Alaska ,  1964
ABSTRACT

Jurassic ammonites of middle Bajocian age occur in the Tuxedni Group along the northwest side of Cook Inlet and in the Tuxedni Formation in the eastern part of the Talkeetna Mountain, Alaska. Numerically the dominant families are the Otoitidae and Stephanoceratidae. The families Phylloceratidae, Sonninidae, Oppelidae, and Perisphinctidae together compose only about one-third of the total specimens.

The Tuxedni Group has not furnished any ammonite genera that characterize the European zone of Sonninia sowerbyi at the base of the middle Bajocian. It has, however, furnished ammonites that characterize the next higher zones of Otoites sauzei and Stephanoceras humphriesianum.

......
Report by: Ralph W. Imlay
Age: Bajocian (middle Bajocian)
Formation: Fitz Creek Siltstone
Comment:Shown as locality 25 in Figure 2.
Occurrence(s)
No. Group Name Qty Notes
1 Ammonoids Oppelia stantoni Imlay, n. sp. One specimen (paratype) from this locality illustrated in Pl. 8, fig. 18