Sample Detail of
Sample: Sample No. 91Tr07A -- USGS No. 31839-PC
Locality: Field No. 91Tr07A
Description: Howard Pass C-3. Lat. 68o 30.7' N., Long. 157o 34.6' W. Sample from 1-ft-diameter block of very finely vuggy, fine- to medium-gray-weathering, very light-gray to creamy dolostone containing thin lenses of black chert along with crinoid columnals >1/4 inch in diameter. From apparent subcrop near top of 30-m-thick section and within 3 m of contact with overlying black chert. Some vugs contain solid hydrocarbons. Thin-section is coarse-crystalline (0.2-0.4 mm) dolostone containing a few skeletal fragments (mostly crinoid ossicles) that may still be calcite. (description from Dover et al., 2004, p. 38 (Table 1)); [Howard Pass C-3 quad. 68°30.69', 157°34.75'. Lisburne Group (Brooks Range allochthon): about one-foot block of fine- to medium-grained, light- to medium-gray-weathering, very finely vuggy, very light-gray to creamy, sugary dolomite containing thin lenses of black chert with >1/4 inch crinoid columnals. From apparent subcrop beneath talus and within 3 m of contact with overlying black chert. About 30 m of the same lithology occurs in the section. Thin-section indicates coarse-crystalline (0.2-o.4 mm) dolostone, with a few skeletal fragments (mostly crinoid ossicles) that may still be calcite. Slide looks like shallow-water dolostone, not Kuna-type. Too dolomitized to distinguish original texture.
From creek southwest of Mt. Bupto. (description from Harris E&R report dated Sept. 17, 1993; Shipment no. A-93-11)]
Location: Alaska Quadrangle: Howard Pass C-3
Lat.: 68o30.7 ' Long.: 157o34.6 '
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: Kinderhookian-Osagean (late Kinderhookian - Osagean (Early Mississippian))
Formation: Lisburne Group (Bupto facies of Lisburne Group (Upper and Lower Mississippian))
CAI:Min: 1.5
Comment:Age: Early Mississippian (late Kinderhookian through Osagean); equivalent in age to the Kuna Formation and part of the Wachsmuth Limestone.

Biofacies: Postmortem transport from or within the polygnathid-hindeodid-pseudopolygnathid biofacies. Represents normal-marine, mid-shelf to upper-slope depositional environment. Shown as locality 66 on Sheet 2; map unit: Mlb

CAI=1.5

Sample only partly picked; conodonts abundant.

Occurrence(s)
No. Group Name Qty Notes
1 Conodonts Hindeodus crassidentatus (Branson and Mehl), 36 Pa and 1 Sc elements All conodonts identified by A.G. Harris
2 Conodonts Kladognathus? sp. indet., 6 Sa and 7 Sc elements
3 Conodonts 75 Pa elements Polygnathus communis communis Branson & Mehl
4 Conodonts 34 Pseudopolygnathus multistriatus Mehl and Thomas
5 Conodonts Unassigned elements: 9 Pb (2 morphotypes), 23 M (5 morphotypes), 2 Sb (2 morphotypes), and 6 Sc (2 morphotypes)
6 Conodonts 32 indet. bar, blade, and platform fragments

Title: Report on Referred Fossils ,  1993 (09/17)
This report is long (1.5 years) overdue, but I have been exceedingly busy writing papers, responding to reviewers and editors comments and preparing talks. I am finally returning to a partial E&R mode and your collections were at the top of the list.
Report by: Anita G. Harris
Referred by: Irv L. Tailleur , John S. Kelley
Age: Kinderhookian-Osagean (late Kinderhookian - Osagean)
Formation: Lisburne Group
CAI:Min: 1.5
Comment:Age: late Kinderhookian through Osagean; this is rather old for the typical platformal Lisburne of the northeast Brooks Range, but is equivalent in age to the Kuna and part of the Wachsmith. This is NOT a Kuna conodont biofacies!!
Biofacies: Postmortem transport from or within the polygnathid-hindeodid-pseudopolygnathid biofacies. Represent normal-marine, mid shelf to upper slope depositional environment.
Thin section description by Julie A. Dumoulin.
CAI = 1.5

Heavy-mineral concentrate is chiefly dolomite and conodonts.

Occurrence(s)
No. Group Name Qty Notes
1 Conodonts Only partly picked; conodonts abundant
2 Conodonts Hindeodus crassidentatus 36 Pa and 1 Sc elements
3 Conodonts Kladognathus? sp. indet. 6 Sa and 7 SC elements
4 Conodonts 75 Pa elements Polygnathus communis communis Branson and Mehl
5 Conodonts 34 Pseudopolygnathus multistriatus Mehl and Thomas
6 Conodonts UNASSIGNED ELEMENTS: 9 Pb (2 morphotypes), 23 M (5 morphotypes), 2 Sb 2 morphotypes), and 6 Sc (2 morphotypes)
7 Conodonts 32 indet. bar, blade, and platform fragments