Beartooth Butte Formation
Appearance
Beartooth Butte Formation | |
---|---|
Stratigraphic range: Lochkovian-Emsian ~ | |
Type | Formation |
Sub-units | Cottonwood Canyon Member |
Lithology | |
Primary | Mudstone, sandstone |
Other | Shale, limestone |
Location | |
Coordinates | 45°00′N 109°36′W / 45.0°N 109.6°W |
Approximate paleocoordinates | 28°12′S 47°06′W / 28.2°S 47.1°W |
Region | Wyoming |
Country | United States |
Type section | |
Named for | Beartooth Butte |
The Beartooth Butte Formation is a geologic formation in Wyoming. It preserves fossils dating back to the Devonian period.[1]
Description
The formation contains a basal limestone conglomerate overlain by evenly bedded red or gray limestones (more accurately, limy mudstones) and calcareous shales. It is a lenticular, channel-fill deposit which is some 2,500 feet (760 m) wide and 250 feet (76 m) thick at maximum. Most collections are from the talus slope. Stable oxygen and isotope data (Poulson in Fiorillo, 2000) indicate that the Beartooth Butte Formation was deposited in an estuarine environment, with the Cottonwood Canyon section being slightly less saline than the type section.
Fossil content
The following fossils have been reported from the formation:[1]
- Fish
- Allocryptaspis ellipticus
- A. flabelliformis
- Anarthraspis chamberlini
- A. montanus
- Bryantolepis brachycephalus
- B. cristatus
- Bryantolepis major
- B. obscurus
- Bulbocanthus rugosus
- Cardipeltis bryanti
- C. richardoni
- Cosmaspis transversa
- Drepanophycus devonicus
- Gosslingia americana
- Lampraspis tuberculata
- Machaeracanthus minor
- Onchus penetrans
- O. peracutus
- Protaspis brevispina
- P. mcgrewi
- Psilophyton wyomingense
- Uranolophus wyomingensis
- Aethaspis sp.
- Cephalaspis sp.
- Simblaspis sp.
- Insects
- Flora
- Invertebrates
See also
References
- ^ a b Beartooth Butte Formation at Fossilworks.org
Bibliography
Categories:
- Geologic formations of Wyoming
- Devonian geology of Wyoming
- Emsian Stage
- Lochkovian Stage
- Pragian Stage
- Limestone formations
- Mudstone formations
- Sandstone formations
- Shale formations
- Shallow marine deposits
- Devonian southern paleotemperate deposits
- Devonian southern paleotropical deposits
- Paleontology in Wyoming