Reference Detail of

Report on Referred Fossils
Edit Reference Add/Edit Sample Sample List Show Map
Stratigraphic range: Upper Triassic and Lower Cretaceous
Kinds of fossils: Marine Mollusks
Quadrangle or area: Sitka (A-2)
Shipment No.: A-59-10
Referred by: Lathram, E. H.
Report prepared by: Silberling, Norman J. , Jones, David L.
Date: 07/21/1959

Report prepared by: N.J. Silberling, 7/21/59 (in collaboration with D.L. Jones)

For your information the following USGS locality numbers have been assigned to the Triassic collections retained from southeastern Alaska shipments A-57-14 and A-58-11 and reported on previously.

USGS Loc. No. - Field No. - Quad.
M509 - 58ALy36 - Sitka B-1
M510 - 58ALy204 - Sitka B-1
M511 - 58ALy221 - Sitka B-1
M512 - 58ALy136b - Sitka B-1
M513 - 58ALy290 - Sitka B-1
M514 - 58ALy330 - Sumdum B-6
M515 - 58ALy494 - Sumdum B-6
M516 - 57ADu62 - Sitka D-1
M517 - 57ADu66 - Sitka D-1
M518 - 57ADu74 - Sitka B-1
M519 - 57ADu75 - Sitka B-1
M520 - 57ADu77 - Sitka B-1
M521 - 57AL101 - Sitka B-1
M522 - 57AL57 - (locality data incomplete)


***
Brief statement of problem and remarks (from collector):
Determination of general age of the material will aid in solution of structural and stratigraphic problems encountered during field mapping currently under way in S. Admiralty Island. At this time, only brief, perhaps informal, period classificiation of collections is desired. Material to be retained by P&S for routine complete report.
User Note module to be added
59ABg5 , Sitka , Sitka A-2 coordinates: 12.51, 8.5(8?). (description from Silbering E&R report) [Transmittal sheet of Lathram dated 6/30/59 provides following description: Thin-bedded, fine grain brownish gray crystalline limestone, interbedded with graywacke and argillites. Associated with chert-pebble conglomerate and breccia, but exact stratigraphic relationships between these and thin-bedded rocks not clear. All units appear to underlie massive gray chert breccia. Fossils (in limestone) possibly Mesozoic/Triassic pelecypod fragments. Sitka A-2 coords: 12.51, 8.5? (last number unclear: comment by R.B. Blodgett)]
Halobia sp. indet.
59ABg5A (Mesozoic loc. M531) , Sitka , Alaska, Admiralty Island. Black carbonaceous limestone interbedded with thin-bedded limestone-graywacke sequence. Sitka A-2 quad.; 12.49 in. perpendicular to W margin, perpendicular intersects W margin 8.55 in. up from SW corner. Coll.: H.C. Berg, 1959. (description from Silberling E&R report) [Transmittal sheet of Lathram dated 6/30/59 provides following description: Black carbonaceous limestone interbedded with thin-bedded limestone-graywacke of 59ABg5. Possibly Mesozoic/Triassic pelecypod fragments. Sitka A-2 coords: 12.49, 8.55]
Halobia cf. H. ornatissima Smith
59ABg6 (Mesozoic loc. M530) , Sitka , Assigned USGS Loc. 530 in my report on shipment of A-59-4M dated 7/20/59. Sitka A-2 coordinates: 12.32, 8.53. (from Silberling E&R report of 7/21/59) [Silberling E&R report of 7/20/59 provides following description: Alaska, Admiralty Island. Near top of thin- to medium-bedded gray limestone that overlies thin-bedded fine-grained brownish gray crystalline limestone; total exposed thickness of limestone exceeds 200 feet. North shore of Herring Bay. Sitka A-2 quad; 12.32 in. perpendicular from west margin, perpendicular intersects west margin 8.53 in. up from SW corner. Coll.: H.C. Berg, 1959][Transmittal sheet of Lathram dated July 13, 1959, provides following description: Ammonites, cephalopods from near top of thin-to-medium-bedded gray ls. that overlies thin-bedded fine-grained brownish gray ls. Entire ls. unit not exposed but thickness exceeds 200 feet. Possibly Mesozoic-Triassic field stratigraphic assignment. Sitka A-2 coords: (12.32, 8.53)] [Transmittal sheet of Lathram dated 6/30/59 provides the following description: Ammonite and uncoiled cephalopod from near top of thin- to medium-bedded gray limestone that appears to underlie 59ABg5 and 5A. Entire limestone unit not exposed, but thickness exceeds 200 feet. Possibly Mesozoic/Triassic field stratigraphic assignment. Sitka A-2 coords: 12.32, 8.53]
Trachyceratid ammonite
Atractites sp.
59AL15 (Mesozoic loc. M532) , Sitka , Alaska, Admiralty Island. Brownish-gray fine-grained fossiliferous calcareous slate interbedded with thin-bedded argillite, graywacke, and conglomerate. Sitka A-2 quad.; 7.37 in. perpendicular from W margin, perpendicular intersects W margin 8.55 in. up from SW corner. Coll.: E.H. Lathram, 1959. (description from Silbering E&R report)[Transmittal sheet of Lathram, dated 6/30/59 provides following description: Brownsih-gray fine grain calcareous slate (fossils), interbedded with thin-bedded argillite, graywack and conglomerate. Unit appears to be in fault contact with, or to lie unconformably above, thick fossiliferous limestone (59ABg40 - see below). Possible pelecypod fragments of Mesozoic/Triassic age. Sitka A-2 coords: 7.37, 3.60](note by R.B. Blodgett: observe discrepancy given in second coordinate between these two sources)
Halobia of the group of species H. septentrionalis, .....
..... H. dalliana, ........
..... and H. symmetrica described by J.P. Smith (1927, USGS Prof. Paper 141)
59APy15 , Sitka , Alaska, Admiralty Island. Intricately fractured, blocky weathering, thin-bedded argillite, graywacke and limestone, containing lenses and layers of dark green-gray volcanic rock. Sitka A-2 quad.; 12.29 in. perpendicular from W margin, perpendicular intersects W margin 8.62 in. up from SW corner. Coll.: J.S. Pomeroy, 1959. Collection discarded. (description from Silbering E&R report) [Transmittal sheet of Lathram dated 6/30/59 provides following description: Intricately fractured, blocky weathering, thin-bedded argillite, graywacke, limestone, containing lenses and layers of dark greenish-gray volcanic rock. Fossils are from dark gray fine grain limestone and calcareous argillite. Possibly Mesozoic/Jurassic-Cretaceous pelecypods. Sitka A-2 coords: 12.29, 8.62]
Buchia cf. B. crassicollis (Keyserling)