Sample Detail of
Sample: Sample No. 92AD35AA -- USGS No. 32441-PC
Locality: Field No. 92AD35AA
Description: Howard Pass B-3. Lat. 68o 19'15" N., Long. 157o 44'10" W. Sample from 4- to 10-cm-thick beds of dark- to medium-dark-gray limestone (calcitized radiolarite?). Thin section is dark, finely intergrown carbonate and silica containing locally abundant brown clasts of noncalcareous mud and scattered, variously preserved radiolarians (some calcite replaced, some pyritized, and some filled with chalcedony). Collected at type locality of Kuna Formation (as designated in Mull and others, 1982); from small outcrop at stream level approx. 15 m west and 12 m topographically lower than base of 92AD35A measured section. If 92AD35AA strata are in place, they are the lowest exposure at the type locality. (description from Dover et al., 2004, p. 50 (Table 1));
[Howard Pass B-3. 68°12'30", 157°44'10". 4-10 cm-thick beds of dark- to medium-dark-gray limestone (calcitized radiolarite?). Collect type section (as designated in 1982 AAPG Bulletin article) of Kuna Fm. of Lisburne Group; from small outcrop right at stream level ~15 m west and 12 m topographically lower than base of 92AD35A measured section (if it is in place, it is the lowest part of section).
Collected from north side of unnamed tributary at headwaters of Safari Creek. ~ 1/3 mile east of main branch of creek and ~2.5 miles west of headwaters of Ipnavik River; NW1/4 sec. 21, T. 34 N., R. 25 W. (description from Harris E&R report dated March 17, 1995)]
Location: Alaska Quadrangle: Howard Pass B-3
Township&Range: 34 N. 25 W. Section: 21
Lat.: 68o19'15 " Long.: 157o44'10 "
Reference
Title: Geologic and fossil locality maps of the west-central part of the Howard Pass Quadangle and part of the adjacent Misheguk Mountains Quadrangle, western Brooks Range, Alaska ,  2004
Report by: Jim Dover , Irv L. Tailleur , Julie A. Dumoulin
Age: Osagean (late Early Mississippian (early middle Osagean))
Formation: Kuna Formation
CAI:Min: 3
Comment:Age: late Early Mississippian; Upper G. typicus Subzone or lower part Sc. anchoralis-Do. latus Zone (early middle Osagean) on the basis of age constraints from overlying sample.

Biofacies: Bispathodid-gnathodid; slope or basin depositional setting.

Shown as locality 147 on Sheet 2; map unit: lPMk

CAI= approx. 3. Organic matter invades or partly covers all conodonts; consequently CAI difficult to determine.

Processed 9.8 kg of rock.

Occurrence(s)
No. Group Name Qty Notes
1 Conodonts Bispathodus utahensis Sandberg and Gutschick (juveniles and adults), 12 Pa, 2 Pb, 7 M, 1 Sa, 3 Sb, and 14 Sc elements All conodonts identified by A.G. Harris
2 Conodonts 30 Pa elements (adults and juveniles) Gnathodus semiglaber Bischoff
3 Conodonts 20 bar fragments (moderately long) "Hindeodella" segaformis Bischoff s.f.
4 Conodonts Digyrate apparatus elements: 2 Pa (2 morphotypes), 1 Pb, 1 M, 1 Sa, 2 Sc
5 Conodonts Unassigned elements: 1 Pa fragment, 19 Pb (+4 morphotypes), 4 M (2 morphotypes), 3 Sa, and 5 Sc
6 Conodonts 70 indet. bar, blade, and platform fragments

Title: Report on Referred Fossils ,  1995 (03/17)
Analysis of all samples is given in the accompanying 16-page table. The range of biostratigraphically important samples is shown on the accompanying diagram. The heavy-mineral concentrates were analyzed by Nancy Stamm; the residues have been returned to Julie Dumoulin. Please note a few (~4 samples have heavy-mineral concentrates that include chalcopyrite and bornite).
Report by: Anita G. Harris
Referred by: Julie A. Dumoulin , J. H. Dover
Age: Osagean (early middle Osagean)
Formation: Kuna Formation
Comment:Age: Upper G. typicus Subzone or lower part anchoralis-latus Zone (early Middle Osagean) on the basis of age constraints from overlying sample.
Biofacies: Bispathodid-gnathodid; slope or basin depositional setting.
CAI = ~3

9.8 kg of rock processed (600 g of +20 mesh and 150 g 20-140 mesh insoluble residue).
Heavy-mineral concentrate: chiefly unpicked conodont fragments covered with organic matter and phosphatized argillaceous grains.

Occurrence(s)
No. Group Name Qty Notes
1 Conodonts Organic matter invades or partly covers all conodonts, consequently CAI difficult to determine.
2 Conodonts Bispathodus utahensis Sandberg and Gutschick (juveniles and adults) 12 Pa, 2 Pb, 7 M, 1 Sa, 3 Sb, and 14 Sc elements
3 Conodonts 30 Pa elements (adults and juveniles) Gnathodus semiglaber Bischoff
4 Conodonts 20 bar fragments (moderately large) "Hindeodella" segaformis Bischoff s.f.
5 Conodonts Digryate apparatus elements 2 Pa (2 morphotypes), 1 Pb, 1 M, 1 Sa, 2 Sc
6 Conodonts UNASSIGNED ELEMENTS: 1 Pa fragment, 19 Pb (+4 morphotypes), 4 M (2 morphotypes), 3 Sa, and 5 Sc
7 Conodonts 70 indet. bar, blade, and platform fragments