Sample Detail of
Sample: Sample No. 91Tr13 -- USGS No. 31841-PC
Locality: Field No. 91Tr13
Description: Hoard Pass C-3. Lat. 68o 31.1' N., Long. 157o 35.5' W. Sample from 2 m of Lisburne Group exposed below diabase sill. Lenticularly interbedded, dark, very fine grained limestone and black chert. Thin section is recrystallized carbonate with little relict texture; one possible crinoid columnal noted and minor disseminated opaque minerals. (description from Dover et al., 2004, p. 36 (Table 1)); [Howard Pass C-3 quad. 68°31.08', 157°36.0'. 2 m of Lisburne Group exposed below diabase sill. Lenticulary interbedded dark, very fine grained limestone and black, lensoidal chert. Ipnavik allochthon--rocks equivalent to the Rim Butte unit of Dumoulin and others (in press). Thin section is recrystallized carbonate with little relict texture; one possible crinoid columnal and minor disseminated opaques.
Outcrop beneath sill on scarp of black at end of high ridge, a few hundred meters north of 91TR09. (description from Harris E&R report dated Sept. 17, 1993; Shipment no. A-93-11)]
Location: Alaska Quadrangle: Howard Pass C-3
Lat.: 68o31.1 ' Long.: 157o35.5 '
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 (middle Osagean (late Early Mississippian))
Formation: Lisburne Group (Rim Butte unit of Lisburne Group of Dumoulin and others (1993) (Mississippian))
CAI:Min: 2
Comment:Age: late Early Mississippian; lower half of Sc. anchoralis-Do. latus Zone (middle Osagean). This species association is typical of Lisburne Group rocks of the Rim Butte unit.

Biofacies: Postmortem hydraulic mixing of mid-shelf to deep-water biofaces.

Shown as locality 59 on Sheet 2; map unit: Mlri

CAI=(approx.) 2 + heavy gray patina

Sample only partly picked; conodonts abundant.

Occurrence(s)
No. Group Name Qty Notes
1 Conodonts 1 Pa element Bispathodus aff. B. utahensis Sandberg and Gutschick All conodonts identified by A.G. Harris
2 Conodonts 3 P elements Eotaphrus burlingtonensis Pierce and Langenheim
3 Conodonts 1 Pa element fragment Gnathodus sp.
4 Conodonts 8 Pa elements Polygnathus communis Branson and Mehl
5 Conodonts 1 Pa element Protognathodus cordiformis Lane, Ziegler, and Sandberg
6 Conodonts 3 Pa elements Pseudopolygnathus nudus Pierce and Langenheim morphotype 2
7 Conodonts 12 Pa element fragments Pseudopolygnathus spp.
8 Conodonts Scaliognathus anchoralis Branson and Mehl 2 Pa and 8 S element fragments
9 Conodonts Unassigned elements: 10 Pb (4 morphotypes), 9 M (2 morphotypes), 1 Sa, and 8 S element fragments
10 Conodonts 44 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: Osagean (middle Osagean)
Formation: Lisburne Group
Comment:Age: lower half of anchoralis-latis Zone, middle Osagean; the species association is typical of Lisburne Group rocks of the Rim Butte unit of the Ipnavik allochthon.
Biofacies: Postmortem hydralic mixing mid shelf to deep water biofacies.
Thin section description by Julie A. Dumoulin.
CAI = ~2 + heavy gray patina

Heavy-mineral concentrate: chiefly fresh and weathered, euhedra and euhedral clasts of pyrite and lesser white tabular to flaky mineral.

Occurrence(s)
No. Group Name Qty Notes
1 Conodonts Only partly picked; conodonts abundant
2 Conodonts 1 Pa element Bispathodus aff. B. utahensis Sandberg and Gutschick
3 Conodonts 3 P elements Eotaphrus burlingtonensis Pierce and Langenheim
4 Conodonts 1 Pa element fragment Gnathodus sp.
5 Conodonts 8 "Hindeodella" segaformis Bischoff s.f. bar fragments
6 Conodonts 8 Pa elements Polygnathus communis Branson and Mehl
7 Conodonts 1 Pa element Protognathodus cordiformis Lane, Sandberg, and Ziegler
8 Conodonts 3 Pa elements Pseudopolygnathus nudus Pierce and Langenheim morphotype 2
9 Conodonts 12 Pa element fragments Pseudopolygnathus spp.
10 Conodonts 2 Pa elements Scaliognathus anchoralis Branson and Mehl
11 Conodonts UNASSIGNED ELEMENTS: 10 Pb (4 morphotypes), 9 M (2 morphotypes), 1 Sa, and 4 Sc (2 morphotypes)
12 Conodonts 44 indet. bar, blade, and platform fragments