Upper Devonian radiolarians separated from chert of the Ford Lake Shale, Alaska

Journal of Research of the U.S. Geological Survey
By: , and 

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Abstract

Leaching of black bedded chert from the Ford Lake Shale, Kandik Basin, Alaska, with dilute hydrofluoric acid resulted in the complete separation of moderately well preserved radiolarians. Preliminary study of an assemblage obtained from the lower half of the formation revealed six to eight forms apparently identical to specimens previously known from the Tournaisian of southern France and northwestern Turkey, including four genera not previously described from North America. Sparse, poorly preserved conodonts in the same sample are of Late Devonian age. We conclude that certain radiolarian species, hitherto known only from the early Carboniferous, span the Devonian-Carboniferous boundary. The radiolarian assemblage of the Ford Lake Shale sample contrasts markedly with Late Devonian assemblages known from the Canol Shale of northern Canada and the Huron Member of the Ohio Shale; the Ford Lake Shale fauna may reflect greater oceanic influences than these other localities, which lie farther inland from the Devonian continental margin.

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Publication type Article
Publication Subtype Journal Article
Title Upper Devonian radiolarians separated from chert of the Ford Lake Shale, Alaska
Series title Journal of Research of the U.S. Geological Survey
Volume 6
Issue 6
Year Published 1978
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Description 14 p.
First page 775
Last page 788
Country United States
State Alaska
Other Geospatial Ford Lake Shale, Kandik Basin, Yukon River
Online Only (Y/N) N
Additional Online Files (Y/N) N
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