Report on Referred Fossils |
|
|
Stratigraphic range: |
Upper Triassic and indeterminate |
Kinds of fossils: |
Marine invertebrates |
Quadrangle or area: |
Talkeetna D-1; Mt. McKinley A-1; Healy A-6 |
Shipment No.: |
A-77-12M |
Referred by: |
Reed, Bruce
|
Report prepared by: |
Silberling, Norman J.
|
Date: |
03/15/1977 |
|
|
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.
|
|
User Note module to be added |
|
76AR198
, Talkeetna
, Elevation 5,020 feet, 1.25 miles east of Swift Creek.
|
|
Cidarid echinoid spines in laminated (foliated?) gray limestone
|
|
|
|
|
76AR199
, Talkeetna
, Elevation 4,150 feet, 1.75 miles east of Swift Creek. Request for Paleo. Analysis form says from "Massive limestone with abundant fossil debris. Unit overlain by gray argillite and siltstone. Thought to be same limestone as 76AR198"
|
|
|
poorly preserved, silicified, questionable coral fragments
|
|
|
|
|
76AR238
, Talkeetna
, Elevation 4,720 feet, 1.5 miles northeast of the Hidden River.
|
|
indeterminate ribbed bivalve
|
|
|
|
|
76ACo47A and B
, Talkeetna
, Elevation 4,900 feet, 1.5 miles east of Swift Creek.
|
|
coarsely silicified and indeterminate corals
|
|
|
|
|
76AR49
, Talkeetna
, Elevation 5,200 feet, 1.5 miles east of Swift Creek. Coral and pelecypod fragments in the same limestone as 76ACo47A, 76ACo47B.
|
|
possible spongiomorph, but too poorly preserved for positive identification
|
|
|
|
|
76ACo50
, Talkeetna
, Elevation 4,100 feet, 1.5 miles east of Swift Creek
|
|
indeterminate large solitary coral
|
|
|
abundant echinodermal debris
|
|
|
|
|
76ACo53
, Talkeetna
, Elevation 4,200 plus feet, 1.5 miles east of Swift Creek.
|
|
poorly preserved branching coral, possiblyThecosmilia
|
|
|
|
|
76ANs58A
, Talkeetna
, Elevation 5,300 feet, 1.75 miles east of Swift Creek.
|
|
|
|
|
76ANs58F
, Talkeetna
, Elevation 4,960 feet, 2.5 miles east of Swift Creek.
|
|
|
|
76ANs58G
, Talkeetna
, Elevation 4,300 feet, 2.5 miles east of Swift Creek.
Elevation 4,300 feet, 2.5 miles east of Swift Creek.
|
|
large micritized shell fragments
|
|
|
|
|
|
76ACo64
, Talkeetna
, Elevation 4,8oo feet, 1.25 miles southwest of the Eldgridge Glacier.
|
|
Molds of calcareous lumps in sheared argillite. Not recognizably organic in origin.
|
|
|
|
|
|
|
|
76ANs54A
, Talkeetna
, Elevation 4,000 feet, 0.5 miles west of Swift Creek.
|
|
Possibly Heterastridium, but too sheared and recrystallized to be certain.
|
|
|
|
|
76AR221
, Talkeetna
, Elevation 4,300 feet, 0.5 miles northwest of Skihi Creek.
|
|
|
|
76AR223
, Talkeetna
, Elevation 3,200 feet, 0.5 miles southeast of Skihi Creek.
|
|
Nothing recognizably organic
|
|
|
|
|
|
76ANs53F
, Talkeetna
, Elevation 4,950 feet, 2.25 miles southwest of the Eldridge Glacier.
|
|
large bivalve shell fragment
|
|
|
molds of star-shaped crinoid columnals in slaty siltstone
|
|
|
|
|
76ANs53G
, Talkeetna
, Elevation 4,950 feet, 2.25 miles southwest of Eldridge Glacier.
|
|
fragment of a large solitary coral
|
|
|
fragment of thick prismatic bivalve shell or an originally aragonitic vein
|
|
|
|
|
76ANs53H
, Talkeetna
, Elevation 4,950 feet, 2 miles southwest of the Eldridge Glacier.
|
|
|
|
76ANs53K
, Talkeetna
, Elevation 4,800 feet, 2 miles southwest of the Eldridge Glacier.
|
|
|
|
76ANs53M
, Talkeetna
, Elevation 4,600 feet, 2 miles southest of the Eldridge Glacier.
|
|
|
|
76ANs55G
, Talkeetna
, Elevation 5,050 feet, 2.5 miles northwest of Buskin Glacier
|
|
echinodermal (probably crinoidal) debris visible in hand specimen
|
|
|
|
|
76ACo45
, Talkeetna
, Elevation 3,850 feet, 1.5 miles southwestof the Eldridge Glacier
|
|
echinodermal (probably crinoidal) bioclasts visible in hand specimen
|
|
|
|
|
76ACo46A
, Talkeetna
, Elevation 3,800 feet, 1.5 miles southwest of the Eldridge Glacier.
|
|
may be fragment of colonial coral
|
|
|
|
|
76ACo46B, C, and D
, Talkeetna
, Elevation 3,540 feet, 1 miles southwest of the Eldridge Glacier
|
|
|
|
|
|
|
|
|
|
|