Sanders Canyon Formation
{{Short description|A geologic formation in New Mexico}}
{{Use American English|date=July 2021}}
{{Infobox rockunit
| name = Sanders Canyon Formation
| image =
| caption =
| type = Formation
| age = Late Eocene
{{Geological range|43|38}}
| period = Eocene
| prilithology = Volcaniclastics
| otherlithology =
| namedfor = Sanders Canyon ({{coord|33.522|N|105.903|W|display=inline}})
| namedby = S.M. Cather
| year_ts = 1991
| region = New Mexico
| country = United States
| coordinates = {{coord|33.507|N|105.857|W|display=inline}}
| unitof =
| subunits =
| underlies = Sierra Blanca Volcanics
| overlies = Cub Mountain Formation
| thickness = {{cvt|150|m||sp=us}}
| extent =
| area =
| map = {{Location map+ | United States#New Mexico
| relief = 1
| width = 250
| float = center
| places =
{{Location map~ | United States#New Mexico
| lat_deg = 33.522
| lon_deg = -105.903
| mark = Orange pog.svg
| marksize = 12
}}
}}
| map_caption =
}}
The Sanders Canyon Formation is a geologic formation exposed north and west of the Sierra Blanca of southern New Mexico. It preserves fossils dating back to the Eocene epoch.{{sfn|Cather|1991|p=269}}
Description
The formation consists of volcaniclastic mudstone (70%) and sandstone (30%), with less sandstone in the higher beds. The grayish-purpose color contrasts with the reddish color of the underlying Cub Mountain Formation and reflects a content of greater than 25% volcanic debris. The upper beds interfinger with the overlying Sierra Blanca Volcanics. Total thickness is about {{convert|150|m||sp=us}} at the type section,{{sfn|Cather|1991|pp=268-269}} but total thickness may be as much as {{convert|400|m||sp=us}}.{{sfn|Koning|Kempter|Zeigler|Cikowski|2011}}
The formation is part of the only extensive exposures of Cretaceous and Paleogene rocks in a large area of south-central and southeastern New Mexico. It is interpreted as sediments deposited by north-northeast-flowing streams. It may correlate with the Palm Park Formation and Rubio Peak Formation, and the overlying Sierra Blanca Volcanics have a maximum age of 38 million years, suggesting the age of the Sanders Canyon Formation is between 43 million and 38 million years.{{sfn|Cather|1991|p=265}}
History of investigation
The formation was first defined by Steven M. Cather in 1991, from beds formerly assigned to the Cub Mountain Formation. The formation was named for Sanders Canyon, just north of the type section.{{sfn|Cather|1991|pp=268-269}}
Footnotes
{{Reflist}}
References
- {{cite journal |last1=Cather |first1=Steven M. |title=Stratigraphy and provenance of upper Cretaceous and Paleogene strata of the western Sierra Blanca Basin, New Mexico |journal=New Mexico Geological Society Field Conference Series |date=1991 |volume=42 |pages=265–275 |url=https://nmgs.nmt.edu/publications/guidebooks/downloads/42/42_p0265_p0275.pdf |access-date=13 July 2021}}
- {{cite journal |last1=Koning |first1=Daniel |last2=Kempter |first2=Kirt |last3=Zeigler |first3=Kate E. |last4=Cikowski |first4=Colin |title=Geologic Map of the Cub Mountain Quadrangle, Lincoln County, New Mexico |journal=New Mexico Bureau of Geology and Mineral Resources Open File Digital Geologic Map |date=2011 |volume=OF-GM 138 |url=https://geoinfo.nmt.edu/publications/maps/geologic/ofgm/downloads/138/OFGM-138_CubMountainReport.pdf |access-date=13 July 2021}}