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Reference
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| Title: |
Report on Referred Fossils
,
1975
(12/11)
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This report deals with four collections of middle Tertiary mollusks and one bone fragment from the Lituya Bay District of southeastern Alaska. |
| Report by: |
Louie Marincovich
, Jr.
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| Referred by: |
George Plafker
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| | Age: | Middle Miocene (probably Middle Miocene) |
| Formation: | Topsy Formtion |
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| Comment: | Age: Probably middle Miocene. The Neptunea has been reported only from the lower Yakataga Formation in the Yakataga District (probably middle Miocene) by Kanno (1971), but its complete stratigraphic range has not yet been veryfied. The Acila species is known in the Yakataga District from the upper Poul Creek Formation (about 700 feet below the top; Clark [1932] and Addicott and others [1971]) and from the lower Yakataga Formation (Kanno, 1971), which probably span the early to middle Miocene. Based on my recent completed monograph of naticid gastropods, the Natica species occurs in middle Miocene to lower Pliocne strata of Oregon and Washinton (lowest occurrence in Astoria and "Chehalis" Formation) and was previously unkown in the Gulf of Alaska Tertiary fauna.
Environment: The genera involved have broad bathymetric ranges, from inner sublittoral (0-100 meters) to upper bathyal (200-2000 meters) depths. Most of the bivalves are articulated but it is not known if they were in living position when collected. Because of the relative abundance of specimens at the samll outcrop, a sublittoral (0-200 meters) site of deposition is suggested. |
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