Bajo Barreal Formation

Bajo Barreal Formation
Bajo Barreal Formation
Stratigraphic range: Mid Cenomanian-Late Turonian; ~
Type	Geological formation
Unit of	Chubut Group
Underlies	Lago Colhué Huapí Formation
Overlies	Castillo Formation
Lithology
Primary	Sandstone
Other	Claystone, mudstone, conglomerate, tuff
Location
Coordinates	45.3°S 69.6°W / -45.3; -69.6
Approximate paleocoordinates	51.6°S 46.7°W / -51.6; -46.7
Region	Chubut, Santa Cruz
Country	Argentina
Extent	Golfo San Jorge Basin
Type section
Named by	Teruggi & Rossetto
Year defined	1963
	Bajo Barreal Formation (Argentina)

The Bajo Barreal Formation is a geological formation in the Golfo San Jorge Basin of Chubut and Santa Cruz, Argentina whose strata date back to the Middle Cenomanian to Late Turonian. The formation was first described by Teruggi & Rossetto in 1963. The sandstones, claystones, mudstones, conglomerates and tuff were deposited in a fluvial environment. The upper part of formation is laterally equivalent to the Yacimiento El Trébol and Meseta Espinosa Formation and the lower part to the Laguna Palacios, Cañadón Seco and Comodoro Rivadavia Formations. The Bajo Barreal Formation is a reservoir rock in the Golfo San Jorge Basin.

Vertebrate paleofauna

Indeterminate abelisauroids and titanosaurs have been recovered from the formation

Dinosaurs reported from the Bajo Barreal Formation
Genus	Species	Stratigraphic position	Material	Notes	Images
Abelisauridae	Indeterminate	Lower	Maxilla	Possibly distinct from Xenotarsosaurus. Estimated to be 6.21 metres (20.4 ft) long, larger than Xenotarsosaurus.
Abelisauridae		Lower	partial skeleton	Different from all other comparable abelisaurids, but can't be compared with Xenotarsosaurus.
Aniksosaurus	A. darwini	Lower		A basal coelurosaur
Andesaurus	A. sp.	Lower		The most basal member of Titanosauria
Campylodoniscus	C. ameghinoi	Lower	Maxilla with seven teeth.
Clasmodosaurus	C. spatula		Jaw with seven teeth	A sauropod
Drusilasaura	D. deseadensis	Upper	"four dorsal vertebrae, one sacral vertebra, six caudal vertebrae, left scapula, dorsal rib fragments, two haemapophyses and indeterminate fragments"	A titanosaur belonging to Lognkosauria
Epachthosaurus	E. sciuttoi	Lower	"Vertebrae [and] partial illium."
Katepensaurus	K. goicoecheai	Lower	Partial skeleton	A rebbachisaurid
Megaraptoridae	Indeterminate	Upper part of lower Lowermost part of upper	Two partial skeletons
Notohypsilophodon	N. comodorensis	Lower	"Vertebrae, partial fore- and hindlimb"
Rebbachisauridae	Indeterminate	Lower	Dorsal vertebra	Different from Katepensaurus.
Sarmientosaurus	S. musacchioi	Lower	A skull	A lithostrotian titanosaur with a skull similar to Brachiosaurus
Xenotarsosaurus	X. bonapartei	Lower	A vertebra and a nearly complete hind limb

Other fossils found in the formation include: