Sample Detail of
Sample: Sample No. 79WG113
Locality: Field No. 79WG113
Description: Rocks at this locality are siliceous-cemented mudstone which is exposed as talus rubble. Locality coordinates: Lat. 62o 05.4'N, Long. 155o 11.3' W; NW1/4 NE1/4 NW1/4, sec. 17, T23N, R32W, McGrath A-5 quadrangle, 1:63,360 scale, 1954 edition. From interbedded fine-grained, siliceous-cemented, clastic rocks and limestones that form the uppermost beds within an unnamed argillite and chert unit, whose total thick probably exceeds 600 m (approx. 2,000 ft). Abundant bryozoans, brachiopods and pelecypods are also found at the same locality. (description from Hahn et al., 1985). [Dutro E&R report of 8/14/80 provides following description: Alaska, McGrath A-5 quad.; NW 1/4 NE 1/4 NW 1/4 sec. 17, T. 23 N., R. 32 W.; silicified limestone lens within uppermost part of unnamed chert-argillite unit. Collector: W. Gilbert, 1979.]
Location: Alaska Quadrangle: Mc Grath A-5
Township&Range: T23N R32W Section: NW1/4, NE1/4, NW1/4 sec. 17
Lat.: 62o05.4 ' Long.: 155o11.3 '
Reference
Title: First recognition of the Gshelian (Upper Pennsylvanian) trilobite Brachymetopos pseudometopina Gauri and Ramovs in North America; and a description of accompanying trilobites from west-central Alaska ,  1985
Report by: Gerhard Hahn , Robert B. Blodgett , Wyatt G. Gilbert
Age: Gzelian (Gshelian (latest Pennsylvanian))
Formation: Unnamed (Unnamed argillite and chert unit)
Comment:Altogether, the Alaskan cephala and pygidia correspond so closely to the type specimens of B. pseudometopina, that they can be included in that species without doubt. In addition, they are probably of the same age. This would imply a latest Pennsylvanian age for strata at locality A-1695.
Occurrence(s)
No. Group Name Qty Notes
1 Trilobites Brachymetopus pseudometopina Gauri and Ramovs
2 Trilobites Pseudophillipsia? (Carniphillipsia) sp. A
3 Trilobites Pseudophillipsia? (Carniphillipsia) sp. B
4 Echinoderms echinoderm debris, indet. identified by J.T. Dutro, Jr.
5 Echinoids Archeocidaris? sp. identified by J.T. Dutro, Jr.
6 Bryozoans fenestrate bryozoans, indet. (molds and casts) identified by J.T. Dutro, Jr.
7 Bryozoans Polypora spp. identified by J.T. Dutro, Jr.
8 Bryozoans stenoporoid bryozoans, indet. (molds and casts) identified by J.T. Dutro, Jr.
9 Brachiopods Septacamera? sp. identified by J.T. Dutro, Jr.
10 Brachiopods Waagenites? sp. identified by J.T. Dutro, Jr.
11 Brachiopods Chonetinella sp. identified by J.T. Dutro, Jr.
12 Brachiopods chonetids, indet. identified by J.T. Dutro, Jr.
13 Brachiopods Anidanthus sp. identified by J.T. Dutro, Jr.
14 Brachiopods Terrakea? sp. identified by J.T. Dutro, Jr.
15 Brachiopods productoid fragments, indet. identified by J.T. Dutro, Jr.
16 Brachiopods Reticularia? sp. identified by J.T. Dutro, Jr.
17 Brachiopods martinioid indet. identified by J.T. Dutro, Jr.
18 Brachiopods punctate spiriferoid, indet. identified by J.T. Dutro, Jr.
19 Bivalves Acanthopecten? sp. identified by J.T. Dutro, Jr.
20 Bivalves pectenoid pelecypods, indet. identified by J.T. Dutro, Jr.
21 Bivalves pelecypod fragments, indet. identified by J.T. Dutro, Jr.

Title: letter ,  1980 (11/01)
To:
Dr. R.B. Blodgett
Oregon State University
Department of Geology
USA - Corvallis, Oregon 97331

1st November 1980

Dear Dr. Blodgett!

Surely you know that Dr. Chamberlain has sent to me your trilobites from Alaska. I have studied them, and I can give you some information concerning their stratigraphical occurrence. Among the specimens of loc. 79WG113 I was able to identify the species Brachymetopus pseudometopina Gauri & Ramovs, 1964 (or a species closely related to the named taxon). This species comes from the Uppermost Carboniferous (Gzhelian) of the Karawanken Mountains in Yugoslavia and Austria. There I suppose that loc. 79WG113 should be group with the Upper Pennsylvanian (Missourian or Virgilian) better than the Mississippian! The trilobite from loc. 77WG203 are so badly preserved that a determination is difficult. Are I allowed to prepare them? Perhaps this will help to win some new information.

The occurrence of Br. pseudometopina in Alaska is very interesting and unexpected, worthy to be published. If you are interested I will write a short paper, photograph the specimens and send the text and plate to you. You can add a notice on the geology and correct my English, and then send the manuscript to the "Journal of Paleontology" for publication. Do you agree?

Yours sincerely,

Prof. Dr. Gerhard Hahn
Philipps-Universitat Marbug
Institut fur Geologie und Palaontologie
Universitatsgebiet Lahnberge
D-3550 Marburg/Lahn
Report by: Gerhard Hahn
Referred by: Robert B. Blodgett
Age: Gzelian (Gzhelian)
Formation: Unnamed
Comment:Among the specimens of loc. 79WG113 I was able to identify the species Brachymetopus pseudometopinaGauri & Ramovs, 1964 (or a species closely related to the named taxon). This species comes from the Uppermost Carboniferous (Gzhelian) of the Karawanken Mountains in Yugoslavia and Austria. Therefore I suppose that loc. 79WG113 should be grouped with the Upper Pennsylvanian (Missourian or Virgilian) better than the Mississippian!
Occurrence(s)
No. Group Name Qty Notes
1 Trilobites Brachymetopus pseudometopina Gauri and Ramovs, 1964 (or a species closely related to the named taxon)

Title: Report on Referred Fossils ,  1980 (08/14)
This report covers 2 collections made by Wyatt Gilbert in the McGrath A-5 quadrangle, west-central Alaska. Both collections are from fine-grained clastic rocks with abundant fenestrate bryozoans, brachiopods, and a few pelecypods. The brachiopods are definitely Permian in age and the association with a variety of bryozoans, including POLYPORA, is characteristic of some parts of the lower Permian sequences elsewhere in the Alaska (for example, the east-central Alaska Range in the lower argillite member of the Eagle Creek Formation, and the Rampart Group of the Tanana-Livengood area).

There are differences between the brachiopod assemblages in these two collections. Collection 77WG203, including the large CHONETINA?, RHYNCHOPORA? AND SPIRIFERELLA sp. may be a bit younger than the other, although differences may reflect environmental factors. In any case, they both appear to be Lower Permian.
Report by: J. Thomas Dutro , Jr.
Referred by: Robert B. Blodgett , Wyatt G. Gilbert
Age: Early Permian
Formation: Unnamed (Unnamed chert-argillite unit)
Comment:There are differences between the brachiopod assemblages in these two collections. Collection 77WG203, including the large CHONETINA?, RHYNCHOPORA? AND SPIRIFERELLA sp. may be a bit younger than the other, although differences may reflect environmental factors. In any case, they both appear to be Lower Permian.
Occurrence(s)
No. Group Name Qty Notes
1 Echinoderms echinoderm debris, indet.
2 Echinoids Archeocidaris? sp.
3 Bryozoans fenestrate bryozoan, indet. (molds & casts)
4 Bryozoans Polypora spp.
5 Bryozoans stenoporoid bryozoans, indet. (molds & casts)
6 Brachiopods Septacamera? sp.
7 Brachiopods Waagenites? sp.
8 Brachiopods Chonetinella sp.
9 Brachiopods chonetids, indet.
10 Brachiopods Anidanthus sp.
11 Brachiopods Terrakea? sp.
12 Brachiopods productoid fragments, indet.
13 Brachiopods Reticularia? sp.
14 Brachiopods martinioid, indet.
15 Brachiopods punctate spiriferoid, indet.
16 Bivalves Acanthopecten? sp.
17 Bivalves pectenoid pelecypod, indet.
18 Bivalves pelecypod fragments, indet.

Title: letter ,  1980 (08/26)
U.S. Geological Survey, Branch of Paleontology and Stratigraphy, 345 Middlefield Road, MS 15, Menlo Park, California 94025

August 26, 1980

To: Mr. Robert B. Blodgett, Department of Geology, Oregon State University, Corvallis, Oregon 97331

Dear Mr. Blodgett:

I have examined your specimens, 79WG113, for microfossil and coral fragments. The limestone has been recrystallized and there are no algae or foraminifera. The corals are solitary forms and are not well preserved. They appear to be belong to the genus Faberophyllum sp. indet. They are of late Meramecian or earliest Chesterian, Mississippian age.

Under separate cover I am returning your specimens.

Sincerely,

Augustus K. Armstrong
Report by: Augustus K. Armstrong
Referred by: Robert B. Blodgett
Age: Meramecian-Chesterian (late Meramecian or earliest Chesterian)
Occurrence(s)
No. Group Name Qty Notes
1 Rugose Corals Faberophyllum sp. indet.