Reference Detail of

Report on Referred Fossils
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Stratigraphic range: Upper Triassic
Kinds of fossils: Marine Invertebrates
Quadrangle or area: Ketchikan A-6
Shipment No.: A-68-6M
Referred by: Berg, Henry C.
Report prepared by: Silberling, Norman J.
Date: 11/18/1968

Transmittal sheet from Berg states: "There are at least 3 apparently contradictory reports (copies attached) on Mesozoic fossil collection from the Bostwick Inlet area of southern Gravina Island. Unfortunately, the maps showing the locations of these early collections are either missing or too sketchy to determine their exact location, and because the area is structurally complex, the reports are virtually useless. The present collections, which are probably at least partly equivalent to some of the early ones, were made during a reconnaissance study of Bostwick Inlet and probably are incomplete. I hope, however, that they will serve as a basis, at least, for working out the stratigraphy & structure of southern Gravina Island.

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68ABg766 (USGS Mesozoic loc. M5093) , Ketchikan , Pelecypods in thin bedded black (carbonaceous) slaty limestone interbedded with siltstone & slate that overlies rhyolitic volcanics to the south. Unit may correlate with with Halobia-bearing black limestone in Threemile Cove on SW Gravina Island. Mid-low tidal zone; about 2.25 miles SSW of Bostwick Point.
Halobia sp. indet.
68ABg767 (USGS Mesozoic loc. M5094) , Ketchikan , Thin to medium bedded gritty, conglomeratic, and locally massive limestone that overlies "Halobia"-bearing beds at 766FMid-upper tidal zone; about 2.20 miles SSW of Bostwick Point
Heterastridium cf. H. conglobatum Reuss
68ABg768 (USGS Mesozoic loc. M5095) , Ketchikan , Pelecypods, brachiopods in thin bedded limestone that overlies "Goofball" bearing beds at 767F. Limestone is about 50 feet thick and is overlain (to north) by fine grained sedimentary rocks and intermediate volcanics. Upper tidal zone; about 2.15 miles SSW of Bostwick Point.
nondescript terebratuloid brachiopods
Gryphaea-like pelecypod
indeterminate small pectenacid pelecypods
one "shape" vaguely suggestive of a coiled cephalopod