Sample Detail of
Sample: Sample No. 96ADb58a
Locality: Field No. 96ADb58a
Description: Charley River A-4 quadrangle, lat 65o 02'21" N., long 142o 33'20" W. Seventymile terrane(?). Greenstone unit gs of Brabb and Churkin (1969); Foster and Keith (1987) remapped the area near this sample and placed it in a greenstone unit that they include in the Seventymile terrane. Sample from metalimestone and metasandstone in 15-m-high cliff. Collected by C. Dusel-Bacon and identified by A.G. Harris. (description from Dusel-Bacon and Harris, 2003, p. 14)
Location: Alaska Quadrangle: Charley River A-4
Lat.: 65o02'21 " Long.: 142o33'20 "
Reference
Title: New occurrences of Late Paleozoic and Triassic fossils from the Seventymile and Yukon-Tanana terranes, east-central Alaska, with comments on previously published occurrences in the same area ,  2003
Abstract - The discovery of several new fossil occurrences of late Paleozoic conodonts and radiolarians in the Seventymile and Yukon-Tanana terranes, and of Late Triassic conodonts in the Seventymile terrane in east-central Alaska, has prompted a reevaluation of other late Paleozoic and Triassic fossils reported in the same areas. The report, in 1995, of giant parafusulinids in the Seventymile terrane within the same stratigraphic interval that more than 20 years before produced poorly preserved Permian brachiopods helped place these beds in the middle Guadalupian and to position the terrane at tropical to subtropical latitudes near ancestral North America during the Middle Permian. .....
Report by: Cynthia Dusel-Bacon , Anita G. Harris
Age: Silurian-Early Triassic (Silurian - Early Triassic, possibly late Paleozoic)
CAI:Min: 5
Comment:Shown as fossil locality 9 on Figure 2

CAI=5, indicating that host rock reached at least 300o C (from p. 14)

Age: Silurian to Early Triassic, possibly late Paleozoic, given the local geologic framework

Remarks: Four of these poorly preserved apatitic fragments are conodonts; the other four fragments may also be conodonts. 7.9 kg of rock was processed; 3.5 kg did not break down. Heavy-mineral concentrate: chiefly weathered pyrite and carbonaceous flakes with finely disseminated pyrite. (from p. 14)

Locality 9 - An outcrop of interlayered slightly metamorphosed carbonate and clastic rocks within a greenstone unit (loc. 9, fig. 2; table 1) included in the Seventymile terrane by Foster and Keith (1987) yielded several conodont fragments that merely provide a generalized age of Silurian to early Triassic. The sample was collected from the northern margin of the peridotite of Mount Sorensen (Foster and others, 1994). The local geologic framework favors a late Paleozoic age. (from p. 18)

Occurrence(s)
No. Group Name Qty Notes
1 Conodonts 4 robust bar fragments
2 Conodonts 4 possible conodont bar fragments