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Reference
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| Title: |
Report on Referred Fossils
,
1969
(12/30)
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This report covers 16 collections of fossils from the Sadlerochit Formation and one ecollection from the upper part of the Lisburne Group. Most of the collections from the Sadlerochit contain elements of an assemblage of brachiopods that is widely distributed in the Permian of the Arctic regions; these collections are invariably from the lower 70 feet of the Sadlerochit. Three collections from the basal beds of the formation contain sparse, atrypical faunas. Two collections from high in the Echooka Member also contain fossils of different aspects. Eight additional collections, from the Ivishak Member and all presumably Triassic in age, were sent to N. J. Silberling for study. BASAL BEDS -- The three collections from basal beds of the Sadlerochit contain abraded fossils, some of which may have been derived from the underlying Lisburne carbonates. Collection 69ADt 34A appears to have a mixture of Pennsylvanian and Permian fosssils, the abraded coral and productoid probably are reworked from older beds. Collection 69ADt 35 has many linguloids, suggesting very shallow water deposition reflacting an onlapping marine situation. ARCTIC PERMIAN ASSEMBLAGE – The brachiopod-rich faunas of the lower 70 feet of the Sadlerochit are composed of only a few common species. Most abundant among these are: Rhynchopora cf. R. nikitini Tschernyschew, Megousia weyprechti (Toula), Muirwoodia sp., Waagenoconcha irginae (Stuckenberg), Spiriferella saranae (de Verneuil), Neospirifer striato-paradoxus (Toula). Similar assemblages are known from the Permian of Arctic Canada, Creenland, Spitzbergen and Novaya Zemlya. Most closely related appear to be the faunas of the Lower Brachiopod Chert of Spitzbergen, the Svalbardian of Stepanov. This is considered equivalent to the lower Kazanian, or earliest Upper Permian by Gobbett (1963) although Harker and Thorsteinsson (1960) place it in the uppermost Lower Permian. There is also a close resemblance between the Sadlerochit fauna and that of the Assistance Formation of Arctic Canada. UPPER ECHOOKA MEMBER – Two collections from high in the Echooka Member contain different species from those in the main Sadlerochit assemblage. Collection 69Adt 28 from Flood Creek has a species of Martinia as its major element. Also present are Paraconularia?, Kochiproductus? and Spiriferella. It is most likely of a Late Permian age. Collection 69Adt 134 (unit 6) contain only bryozoans and Permophricadothyris sp., but it is also of Permian age. |
| Report by: |
J. Thomas Dutro
, Jr.
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| Referred by: |
Robert L. Detterman
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| | Age: | Late Permian |
| Formation: | Echooka Formation |
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| Comment: | It is most likely of a Late Permian age. |
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