| Lotena Formation | |
| Type: | Geological formation |
| Period: | Oxfordian |
| Age: | Late Callovian-Early Oxfordian ~ |
| Prilithology: | Sandstone, conglomerate |
| Otherlithology: | Limestone, shale |
| Namedfor: | Cerro Lotena |
| Namedby: | Weaver |
| Year Ts: | 1931 |
| Region: | Neuquén Basin Mendoza Province & Neuquén Province Northern Patagonia |
| Country: | Argentina |
| Coordinates: | -38.6°N -70.2°W |
| Paleocoordinates: | -35.9°N -31.7°W |
| Unitof: | Lotena Group |
| Subunits: | La Estrechura, El Pichanal & El Vado Members |
| Underlies: | La Manga Formation |
| Overlies: | Cuyo Group Lajas Formation |
| Thickness: | 50- |
| Extent: | 2500km2 |
The Lotena Formation is a geologic formation dated from the Late Callovian to Early Oxfordian in the Neuquén Basin in Mendoza Province, Argentina.[1] The formation, first defined by Weaver in 1931 and named after Cerro Lotena,[2] consists of fluvial conglomerates, calcareous sandstones and marine limestones and shales.[2] [3] The Lotena Formation is overlain by the La Manga Formation and overlies the Lajas Formation of the Cuyo Group.[4] Initially, the fossil find of the pterosaur Herbstosaurus pigmaeus was reported from the formation,[5] but this fossil was found in the younger Vaca Muerta.[6] The formation is a reservoir rock in the Neuquén Basin.