Sample Detail of
Sample: Sample No. 92AD29-8 -- USGS No. 12462-SD
Locality: Field No. 92AD29-8
Description: Howard Pass B-5. Lat. 68o 29'43" N., Long. 158o 35'00" W. Sandy(?) dolostone interlayered with chert bands. Thin section is dolostone containing rare relict crinoid ossicles and thin phosphatic shells; dolomite crystals less than or equal to 120 microns. Collected from unnamed Devonian limestone, at least 12 m stratigraphically below 92AD28A-4. (description from Dover et al., 2004, p. 44 (Table 1)); [Howard Pass B-5. 68°29'43", 158°35'05". Sandy(?) dolostone with chert bands. Collected from unnamed Devonian limestone, at least 12 m stratigraphically below 92AD28A-4.
Collected between 92AD44D and 92AD45 on north-south segment of NW-trending ridge, ~1.75 miles due east of Wager Creek, ~0.5 mile due west of the headwaters of Twistem Creek, western Brooks Range; N. part sec. 13, T. 11 S., R. 29 W. (description from Harris E&R reports dated Jan. 25, 1995 (Shipment no. A-95-3a) and March 17, 1995 (Shipment no. A-95-3)]
Location: Alaska Quadrangle: Howard Pass B-5
Township&Range: 11 S. 29 W. Section: 13
Lat.: 68o29'43 " Long.: 158o35'00 "
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: Eifelian-Givetian (Eifelian - earliest Givetian (middle Middle Devonian))
Formation: Unnamed (Unnamed limestone (Devonian))
CAI:Min: 3
Comment:Age: middle Middle Devonian; Po. costatus costatus Zone through Po. ensensis Zone (upper part of range limited by age of overlying collections; Eifelian, but not very earliest Eifelian, into earliest Givetian.

Biofacies: Indeterminate (too few conodonts); undoubtedly within, or transported from, polygnathid biofacies; possibly near limit of environmental tolerance of polygnathids as all conodonts are small.

Shown as locality 74 on Sheet 2; Map unit: Dl

CAI=3

Occurrence(s)
No. Group Name Qty Notes
1 Conodonts 3 Belodella sp. elements All conodonts identified by A.G. Harris
2 Conodonts Polygnathus linguiformis linguiformis Hinde, 7 Pa, 2 Pb, 3 M, 1 Sa and 1 SB elements
3 Conodonts 41 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: Eifelian (Eifelian, but not very earliest Eifelian)
Formation: Unnamed (unnamed Devonian limestone)
CAI:Min: 3
Comment:Age: Po. costatus costatus Zone through Po. ensensis Zone (upper part of range limited by age of overlying samples); = Eifelian, but not very earliest Eifelian.
Biofacies: Indeterminate (too few conodonts); undoubtedly within or transported from polygnathid biofacies; possibly near limit of environmental tolerance of polygnathids as all conodonts are small.
CAI 3

Heavy-mineral concentrate: chiefly dolomite rhombs and minor iron oxides.

Occurrence(s)
No. Group Name Qty Notes
1 Conodonts 3 Belodella sp. elements
2 Conodonts Polygnathus linguiformis linguiformis Hinde 7 Pa, 2 Pb, 3 M, 1 Sa and 1 Sb elements
3 Conodonts 41 indet. bar, blade, and platform fragments

Title: Report on Referred Fossils ,  1995 (01/25)
All conodont analyses and samples and residue weights are given in the attached tables. The age range of all samples is graphically shown on the accompanying diagram.

Please give a copy of this report to Jim Dover and anyone else on the Howard Pass project that needs these data. I will do all the Carboniferous samples while in Florida.
Report by: Anita G. Harris
Referred by: Julie A. Dumoulin
Age: Eifelian (Eifelian, but not very earliest Eifelian)
Formation: Unnamed (unnamed Devonian limestone)
CAI:Min: 3
Comment:Age: P. costatus costatus Zone through Po. ensensis Zone (upper part of range limited by age of overlying samples); = Eifelian, but not very earliest Eifelian.
Biofacies: indeterminate (too few conodonts); undoubtedly within or transported from polygnathid biofacies; possibly near limit of environmental tolerance of polygnathids as all conodonts are small.
CAI=3

Heavy-mineral concentrate: chiefly dolomite rhombs and minor iron oxides.
Wgt. (kg) 6.5; >20 mesh insol. res., (grams) 620; 20-200 mesh insol. res., (grams) 140

Occurrence(s)
No. Group Name Qty Notes
1 Conodonts 3 Belodella sp. elements
2 Conodonts Polygnathus linguiformis linguiformis Hinde 7 Pa, 2 Pb, 3 M, 1 Sa & 1 Sb elements
3 Conodonts 41 indet. bar, blade, and platform fragments