Lotena Formation

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.

Lotena Formation Stratigraphic range: Late Callovian-Early Oxfordian ~165–160 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Type	Geological formation
Unit of	Lotena Group
Sub-units	La Estrechura, El Pichanal & El Vado Members
Underlies	La Manga Formation
Overlies	Cuyo Group  Lajas Formation
Thickness	50–167 m (164–548 ft)
Lithology
Primary	Sandstone, conglomerate
Other	Limestone, shale
Location
Coordinates	38.6°S 70.2°W / -38.6; -70.2
Approximate paleocoordinates	35.9°S 31.7°W / -35.9; -31.7
Region	Neuquén Basin  Mendoza & Neuquén Provinces   Northern Patagonia
Country	Argentina
Extent	2,500 km2 (970 sq mi)
Type section
Named for	Cerro Lotena
Named by	Weaver
Year defined	1931
Lotena Formation (Argentina)