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Reference
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| Title: |
Report on Referred Fossils
,
1964
(06/30)
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This report is based upon three collections from the type section of the Calico Bluff Formation at Calico Bluff, Yukon River, Alaska. They were collected by E. Wayne Bamber of the Canadian Geological Survey and presented to the U.S. Geological Survey for its use. |
| Report by: |
Mackenzie Gordon
, Jr.
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| Referred by: |
E. Wayne Bamber
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| | Age: | Mississippian-Pennsylvanian (Late Mississippian - or Early Pennsylvanian) |
| Formation: | Calico Bluff Formation |
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| Comment: | These supplement collections made at approximately the same time by Michael Churkin of the USGS. They appear to have come from approximately the same stratigraphic horizon as USGS coll. 21612-PC. These collections contain more of the goniatited specimens than those of Churkin. Several of these have provided fairly undistorted sutures and they appear more like those of Glaphytites than of Cravenoceras. also it appears from these specimens that the surface sculpture resembling that of Cravenoceras appears to be present commonly on internal molds which have adhering to them fragments of altered shell material that appear to be relatively smooth on the outside. It is therefore possible that the same species may appear to have two different types of sculpture. Nevertheless, one cannot say from the material at hand that Gravenocears is not present. Moreover, the genus we are calling Glaphyrites has been found in the Eumorphoceras bisulcatum zone of Spain, associated with Cravenoceras. So we are as yet no farther toward a decision as to whether these beds are Late Mississippian or Early Pennsylvanian in age.
In the lists below are several orthoconic nautiloids not found by the USGS geologists. The one identified as Dolorthoceras? is a small species with fairely shallow camerae, crushed so that the siphuncle has been destroyed. The septal necks are short and curved but not visibly recurved, nor do they project straight apicad. The species identified as Kionoceras? sp. consists of flattened living chambers of a form resembling Kionoceras? sp. D from the Alapah Limestone, described by Gordon in USGS Prof. Paper 283, except that the wavy sculpture appears a strifle coarser. The one identified as Mitorthoceras is a similarly compressed living chamber ornamented by fine transverse threads. |
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