Sample Detail of
Sample: Sample No. 92AD59A -- USGS No. 32452-PC
Locality: Field No. 92AD59A
Description: Howard Pass C-5. Lat. 68o 35'45" N., Long. 158o 27'20" W. Sample from 3- to 6-cm-thick bed of fine-grained, dark-gray, very light gray to medium-gray-weathering, very fetid limestone that has a ghostly texture of black spheroids (calcitized radiolarians?). Thin section is calcite crystal mosaic that contains relict, carbonate-replaced radiolarians. Sample taken approx. 3 m below top of approx. 30-m-thick section (poorly exposed and could be folded) mostly black chert (and (or) silicified mudstone) but including silty bands and spicules and approx. 20-30 percent limestone. Uppermost part of section is light-gray chert that contains radiolarians of Mississippian? age (92AD59G, table 2). (description from Dover et al., 2004, p. 31 (Table 1)); [Howard Pass C-5. 68°35'48", 158°27'25". 3-6 cm-thick-bedded, fine-gray, very light-gray- to medium-gray-weathering, very fetid limestone with ghostly texture of black spheroids (calcitized radiolarians?).
Collected from Mississippian "deeper-water facies" of the Lisburne, ~3 m below top of ~ 30 m(?)-thick section (poorly exposed and could be folded) comprised mostly of black chert (and/or silicified mudstone) with silty bands and spicules and ~20-30% limestone. Uppermost part of section is light-gray radiolarian chert.
Collected from NW side of small knob (~660 m+ high), ~1.5 miles SE of junction of Kiligwa River and Drenchwater Creek; NE1/4NE1/4 sec. 9, T. 10 S., R. 29 W. (description from Harris E&R report dated March 17, 1995; shipment no. A-95-3)]
Location: Alaska Quadrangle: Howard Pass C-5
Township&Range: 10 S. 28 W. Section: 9
Lat.: 68o35'45 " Long.: 158o27'20 "
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-Meramecian (late Osagean - Meramecian (late Early-early Late Mississippian))
Formation: Kuna Formation
CAI:Min: 1.5 - Max: 2
Comment:Age: late Early-early Late Mississippian; Po. mehli-lower G. texanus Zone through Lower Cavusgnathus Zone (late Osagean through Meramecian) on the basis of conodonts in underlying sample (92AD59AA); probably late Osagean.

Biofacies: Indeterminate (too few conodonts); mid-shelf or deeper water depositional environment.

Shown as locality 21 on Sheet 2; map unit: lPMk

CAI=1.5-2

Processed 8.8 kg of rock

Occurrence(s)
No. Group Name Qty Notes
1 Conodonts 2 Pa element fragments Gnathodus pseudosemiglaber Thompson and Fellows? All conodonts identified by A.G. Harris. All conodonts partly coated and invaded by organic matter.
2 Conodonts Unassigned elements: 2 Pb (2 morphotypes), 1 digyrate Pb? of Osagean morphotype, 1 Sa, and 1 Sc
3 Conodonts 42 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-Meramecian (late Osagean - Meramecian, probably late Osagean)
Formation: Lisburne Group (Mississippian "deeper water facies" of the Lisburne Group)
CAI:Min: 1.5 - Max: 2
Comment:Age: Lower G. texanus Zone through Lower Cavusgnathus Zone (=late Osagean through Meramecian) on the basis of conodonts in underlying sample (92AD59AA); probably late Osagean.
Biofacies: Indeterminate (too few conodonts); mid-shelf or deeper water depositional environment.
CAI = 1.5-2

8.8 kg of rock process (580 g of +20 mesh and 90 g 20-140 mesh insoluble residue).
Heavy-mineral concentrate: chiefly phosphatized argillaceous grains and bioclasts and minor iron oxides.

Occurrence(s)
No. Group Name Qty Notes
1 Conodonts all conodonts partly coated and invaded by organic grunge.
2 Conodonts 2 Pa element fragments Gnathodus pseudosemiglaber Thompson and Fellows?
3 Conodonts UNASSIGNED ELEMENTS: 2 Pb (2 morphotypes), 1 digyrate Pb? of Osagean morphotype, 1 Sa, and 1 Sc
4 Conodonts 42 indet. bar, blade, and platform fragments