Caballero Formation
| Caballero Formation | |
|---|---|
| Stratigraphic range: | |
| Type | Formation |
| Underlies | Lake Valley Limestone |
| Overlies | Percha Shale |
| Lithology | |
| Primary | Limestone |
| Other | Shale |
| Location | |
| Coordinates | Lua error: callParserFunction: function "#coordinates" was not found. |
| Region | New Mexico |
| Country | United States |
| Type section | |
| Named by | L.R. Laudon and A.L. Bowsher |
| Year defined | 1941 |
Caballero Formation (New Mexico) | |
The Caballero Formation is a geologic formation found in the highlands flanking the southern Rio Grande River valley in New Mexico. It preserves fossils dating back to the Tournasian Age of the Carboniferous period.[1]
Description
[edit | edit source]The Caballero Formation consists of nodular gray argillaceous limestone, which grades upward into nodular gray marl with shale lenses. It rests conformably on the Percha Shale and is overlain unconformably by the Lake Valley Limestone. The formation likely correlates with the Chouteau Limestone of the upper Mississippi valley.[1]
Fossils
[edit | edit source]The formation is locally abundant in fossils of Tournasian age,[1] with more than 200 marine invertebrate species reported.[2] These include the ammonoids Pericyclus blairi, P. Cooperi P. costulatus, and Gattendorfia bransoni as well as Tournasian conodont and brachiopod faunas.[3] The fauna changes significantly from the westernmost to easternmost exposures of the formation.[2]
History of investigation
[edit | edit source]The beds forming this unit were originally included in the Devonian Percha Shale, but were separated into their own formation by Laudon and Bowsher in 1941, when it was recognized that they are Mississippian in age.[1]
See also
[edit | edit source]Lua error in mw.title.lua at line 392: bad argument #2 to 'title.new' (unrecognized namespace name 'Portal').
References
[edit | edit source]- ^ a b c d Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).