{{Short description|Geologic formation in New Mexico, US}} {{Infobox rockunit | name = Zuni Sandstone | image = Dowa Yalanne.jpg | caption = Type locality of Zuni Sandstone at Dowa Yalanne | type = Formation | age = {{Geological range|middle Jurassic}} | period = middle Jurassic | prilithology = Sandstone | otherlithology = | namedfor = Zuni Plateau | namedby = Clarence Dutton | year_ts = 1885 | region = New Mexico | country = United States | coordinates = {{coord|35.0525|N|108.7957|W|display:inline}} | unitof = | subunits = San Rafael Group | underlies = Dakota Formation | overlies = Chinle Group. Wingate Sandstone | thickness = {{convert|150|m|feet|abbr=on}} | extent = | area = | map = {{Location map+ | United States#New Mexico | relief = 1 | width = 250 | float = center | places = {{Location map~ | United States#New Mexico | lat_deg = 35.0525 | lon_deg = -108.7957 | mark = Cyan pog.svg | marksize = 12 }} }} | map_caption = }}
[[File:Zuni Sandstone El Malpais.jpg|thumb|Outcrop of Zuni Sandstone at El Malpais National Monument, New Mexico]]
The '''Zuni Sandstone''' is a geologic formation in west-central New Mexico. It marks the southernmost limit of Jurassic fluvial and lacustrine sedimentary formations, which pinch out to leave a single sandstone body.
==Description== The Zuni Sandstone is found south of the I-40 corridor in west-central New Mexico. At about this latitude, the Todilto, Morrison, and Summerville Formations pinch out to leave a Jurassic section that is almost entirely composed of eolian sandstone. This is designated as the Zuni Sandstone, which is thus the lateral equivalent of the combined Entrada and Bluff Formations.<ref name="lucas-2020">{{cite journal |last1=Lucas |first1=Spencer G. |author-link1=Spencer G. Lucas |title=Jurassic stratigraphy of the southeastern Colorado Plateau, west-central New Mexico: 2020 synthesis |journal=New Mexico Geological Society Special Publication |date=2020 |volume=14 |pages=135-144 |url=https://nmgs.nmt.edu/publications/special/14/NMGS_SP-14.pdf |access-date=30 October 2020}}</ref>
At the type section at Dowa Yalaane (Taaiyalone Mesa), the formation consists of about {{convert|80|m|feet|sp=us}} of eolian sandstone corresponding to the Entrada Formation. A break corresponds to the pinched-out Todilto and Summerville Formations. Above this is about {{convert|60|m|feet|sp=us}} of sandstone corresponding to the Bluff Formation. Then comes a break corresponding to the pinch-out of the Recapture Member of the Morrison Formation, another sandstone interval corresponding to the Acoma Tongue of the Zuni Sandstone, and a final break corresponding to the pinchout of the remaining Morrison Formation. The Zuni Formation unconformably rests on the Wingate Sandstone or Chinle Group and is unconformably overlain by the Dakota Formation.<ref name="anderson-1983">{{cite journal |last1=Anderson |first1=O.J. |year=1983 |title=Preliminary report on redefinition of Zuni Sandstone, west-central New Mexico |journal=New Mexico Geology |volume=5 |number=3 |pages=56-60 |url=https://geoinfo.nmt.edu/publications/periodicals/nmg/5/n3/nmg_v5_n3_p56.pdf |access-date=29 October 2020}}</ref><ref name="lucas-2020"/>
==History of investigation== The unit was first described by Clarence Dutton in 1885.<ref>{{cite journal |last1=Dutton |first1=C.E. |author1-link=Clarence Dutton |year=1885 |title=Mount Taylor and the Zuni plateau |journal=U.S. Geological Survey Annual Report |volume=6 |pages=113-198 |url=http://pubs.er.usgs.gov/pubs/ar/ar6 |access-date=29 October 2020 }}{{Dead link|date=October 2025 |bot=InternetArchiveBot }}</ref> However, A.A. Baker, C.H. Dane, and J.B. Reeside regarded it as identical to the Morrison Formation.<ref>{{cite journal |last1=Baker |first1=A.A. |last2=Dane |first2=C.H. |last3=Reeside |first3=J.B. Jr. |title=Correlation of the Jurassic formations of parts of Utah, Arizona, New Mexico, and Colorado |journal=U.S. Geological Survey Professional Paper |date=1936 |volume=183 |doi=10.3133/pp183|doi-access=free }}</ref> R.J. Hackman and A.B. Olson renamed the beds as the Cow Springs Sandstone in 1977<ref>{{cite journal |last1=Hackman |first1=R.J. |last2=Olson |first2=A.B. |year=1977 |title=Geology, structure, and uranium deposits of the Gallup 1 degree x 2 degrees quadrangle, New Mexico and Arizona |journal=U.S. Geological Survey Miscellaneous Investigations Series Map |volume=I-981 |url=http://ngmdb.usgs.gov/Prodesc/proddesc_9849.htm |access-date=29 October 2020 |archive-date=1 June 2019 |archive-url=https://web.archive.org/web/20190601075620/https://ngmdb.usgs.gov/Prodesc/proddesc_9849.htm |url-status=dead }}</ref> O.J. Anderson proposed the modern definition of the formation in 1983.<ref name="anderson-1983"/>
==References== {{Reflist}}
Category:Jurassic formations of New Mexico Category:Sandstone formations of the United States