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Reference
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| Title: |
Report on Referred Fossils
,
1977
(12/27)
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| Report by: |
Weldon W. Rau
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| Referred by: |
George Plafker
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| | Age: | Late Eocene-Oligocene |
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| Comment: | Age: Late Eocene or Oligocene (Refugian or Zemorrian Stage)
Remarks: The listed fauna has either been observed or removed from a relatively light and punky siltstone. All specimens, except the arenaceous foraminifers, are either casts or molds and usually pyritized. Identificantions are therefore limited and tentative.
Mainly because identifications are uncertain this fauna is not greatly diagnostic of age. However, based on this aggregation of general morphologic forms, a late Eocene or Oligocene age (Refugian or Zemorrian Stage) is suggested. If Anomalina, Spheroidina, and M. pompillioides in particular are correctly identified the evidence would be fair to good that the assemblage is Zemorrian or younger in age. The evidence in general is good that the assemblage is no older than Refugian but it could possibly be as young as the Saucesian Stage but probably no younger.
Paleoecology: Paleoecologic conditions are perhaps somewhat more strongly indicated by this assemblage than age. It most likely lived in cold water at depths no less than that of outer shelf. Optimum depth may have been middle to upper slope (mid to upper bathyal). The absence of Elphidiids or other shallow water forms, so common in many of the Yakataga faunas, is additional evidence that this fauna probably came from pre-Yakataga rocks. |
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