Frænkelryggen Formation
Geologic formation in Svalbard, Norway
From Wikipedia, the free encyclopedia
The Frænkelryggen Formation is a geologic formation in Svalbard, Norway. The fluvial sandstones and green shales preserve flora and early fish fossils dating back to the Lochkovian stage of the Early Devonian period.
| Frænkelryggen Formation | |
|---|---|
| Stratigraphic range: Lochkovian | |
| Type | Formation |
| Unit of | Red Bay Group |
| Underlies | Ben Nevis Formation |
| Overlies | Andréebreen Formation |
| Lithology | |
| Primary | Sandstone |
| Other | Shale |
| Location | |
| Coordinates | 79.7°N 12.5°E |
| Approximate paleocoordinates | 6.3°N 17.9°W |
| Region | Svalbard |
| Country | Norway |
| Type section | |
| Named for | Frænkelryggen (583 m (1,913 ft)) |
| Named by | Kiaer |
| Year defined | 1918 |
  Frænkelryggen Formation (Svalbard) | |
Description
Defined at the Frænkelryggen mountain (583 m (1,913 ft)) by Kiaer in 1918,[1] the formation was originally described as Silurian,[2] later dating of the formation provided likely ages between 413.5 and 411 Ma, dating the formation to the Lochkovian stage of the Early Devonian.[3] The formation belongs to the Red Bay Group, conformably overlying the Andréebreen Formation and overlain conformably by the Ben Nevis Formation.[4]
The formation comprises sandstone and green shales deposited in a fluvial environment.
Fossil content
The Frænkelryggen Formation has provided fossils of:[2][5]
Vertebrates
- Anglaspis insignis[6]
- Dinaspidella robusta[7]
- Poraspis brevis[8]
- P. polaris[9]
- Machairaspis sp.[10]
- Waengsjoeaspis sp.[10][11]
Flora
- Calamospora nigrata
- Cyclogranisporites plicatus
- Emphanisporites minutus
- Granulatisporites muninensis
- Leiotriletes parvus
- Pachytheca cf. fasciculata
- Punctatisporites glabar
- ?Taeniocrada spitsbergensis
- Prototaxites sp.
- ?Zosterophyllum sp.
- Hostinella indet.