| Juana Lopez Member | |
|---|---|
| Stratigraphic range: | |
 Juana Lopez Member near its reference section south of Cuba, New Mexico | |
| Type | Member |
| Unit of | Mancos Shale (San Juan basin) Carlile Formation (Denver and Raton Basins) Benton Shale (North Park Basin) |
| Underlies | Niobrara Formation |
| Overlies | Codel Sandstone member of the Carlile |
| Thickness | 140 feet (43 m) |
| Lithology | |
| Primary | Sandstone with abundant carbonate fossil grains |
| Other | Gravel, Codel fragments |
| Location | |
| Coordinates | 35°29′12″N 106°12′04″W / 35.4866°N 106.2010°W |
| Country |  United States |
| Type section | |
| Named for | Mesita Juana Lopez Grant, six miles northwest of Los Cerrillos, New Mexico |
| Named by | Rankin |
| Year defined | 1944 |
  Juana Lopez Member (the United States)  Juana Lopez Member (New Mexico) | |
Juana Lopez refers to both the uppermost member of the Carlile Shale formation and to the environment that caused it to form. The Juana Lopez Member is calcareous sandstone dated to the Turonian age of the Upper Cretaceous and is exposed in the southern and western Colorado, northern and central New Mexico,[1] and northeastern Utah.[2] The unit has been described as "the most enigmatic" member of the Carlile Shale.[3]
- ^ Lewis, Russell K. (2013), Stratigraphy and depositional environments of the Late Cretaceous (Late Turonian) Codell sandstone and Juana Lopez members of the Carlile shale, southeast Colorado, Mines Theses & Dissertations, retrieved 2018-08-14
- ^ Molenaar, C.M.; Cobban, W.A. (1991). "Middle Cretaceous stratigraphy on the south and east sides of the Uinta Basin, northeastern Utah and northwestern Colorado". United States Geological Survey Bulletin. 1787-P. doi:10.3133/b1787P.
- ^ Lewis 2013.