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Reference
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| Title: |
Report on Referred Fossils
,
1977
(03/15)
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This report treats the 36 collections that are included in Groups B and C on the transmittal forms. Those collections that contain recognizable, reasonably age-diagnostic fossils are all of late Norian (late Late Triassic) age. From our understanding of the stratigraphic section on strike north-east of the Eldridge Glacier in the Healy Quadrangle, rocks of this age from the uppermost part of the red-bed unit and the lower part of an intergradational but stratigraphically overlying unit of brown calcareous andstone and argillite. The conspicuou limestone and basalt unit stratigraphically underlies the red beds, but it is evidently still no older than Late Triassic. In the Healy (A-6) Quadrangle most of the Triassic rocks above the structually highest serpentine belt on the ridge northeast of Partin Creek are demonstrably overturned.
Thin sections of limestone 76ANs55G, 76ACo45, 46A through -46D, 76ANs57A, and 76AR240 are being prepared. If anything diagnostic appears in them, I will let you know. Your thin sections and their corresponding rocks samples are being returned. Otherwise all of the material, except for that assigned USGS Mesozoic locality numbers, has been discarded. |
| Report by: |
Norman J. Silberling
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| Referred by: |
Bruce Reed
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| | Age: | Norian (late Norian) |
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| Comment: | According to Request for Paleontological Analysis form submitted by Reed, this locality is from his Group C, consisting of 15 collections from rocks presently assigned to the "limestone-basalt"unit. The dominant lithologies of the unit in this area however, are clastic sedimentary rocks--chiefly calcareous graywacke sandstone and siltstone. Interbedded limestone and basalt are present--but are much more abundant in the unit northeast of the Eldridge Glacier. Same form states collection is from "light brown calcareous sandstone with possible cephalopods (and corals). This is a distinctive type of fossil occurrence which we call the "Easter egg" sandstone. |
| Occurrence(s) |
| No. |
Group |
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Name |
Qty |
Notes |
| 1 |
Hydrozoans |
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Heterastridium sp. |
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Heterastridium is the correct name for the spherical hydrozoans, sometimes known as Triassic "goof balls", that apparently form the "eggs" in your "East egg" sandstone such as at field loc. 76ANs53H |
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