Lohan Cura Formation

The Lohan Cura Formation is a geologic formation with outcrops in the Argentine provinces of Río Negro, Neuquén, and Mendoza. It is the second oldest Cretaceous terrestrial formation in the Neuquén Basin.

Lohan Cura Formation
Stratigraphic range: Late Aptian-Albian ~117–100 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Type	Geological formation
Sub-units	Puesto Quiroga & Cullín Grande Members
Underlies	Río Limay Subgroup  Candeleros Formation
Overlies	Mendoza Group  La Amarga, Agrio & Bajada Colorada Formations
Thickness	177 m (581 ft)
Lithology
Primary	Mudstone, siltstone, sandstone
Other	Claystone
Location
Coordinates	39.6°S 69.4°W / -39.6; -69.4
Approximate paleocoordinates	43.7°S 39.4°W / -43.7; -39.4
Region	Río Negro Province, Mendoza Province, Neuquén Province
Country	Argentina
Extent	Neuquén Basin
Type section
Named by	Leanza & Hugo
Year defined	1995
Lohan Cura Formation (Argentina)

The Lohan Cura Formation unconformably overlies the terrestrial La Amarga Formation. In some places it also overlies the older marine Agrio and Bajada Colorada Formations of the Mendoza Group through the same Middle Miranican unconformity. It is in turn overlain by the Candeleros Formation of the Neuquén Group, separated by the Main Miranican unconformity. The Lohan Cura correlates with the Rayoso Formation in some areas.^[1]

Subdivision

The Lohan Cura Formation contains two members of roughly equal thickness. The lowermost member, Puesto Quiroga Member is approximately 85 metres (279 ft) thick. The lowest sediments in this unit are conglomerates, overlain by sandstones and siltstones. The upper two-thirds of the member consists mainly of shales. The Cullín Grande Member is the upper member within the formation, about 92 metres (302 ft) thick, which contains numerous sandstones displaying evidence of stream channels. Near the top of the sequence, siltstones and claystones become dominant.

Fossil content

Numerous tetrapod fossils have been recovered from the Cullín Grande Member of the Lohan Cura, including:

• several turtles (including 2 species of Prochelidella)
• rebbachisaurid sauropods (including Agustinia and Comahuesaurus)
• Ligabuesaurus

The rebbachisaurid Rayososaurus comes from the correlating Rayoso Formation in this same area.

Color key Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon		Notes Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Dinosaurs of the Lohan Cura Formation
Genus	Species	Presence	Notes	Images
Agustinia[2]	A. ligabuei[2]	Neuquén Province[2]	Dorsal sacral and caudal neural arches, hindlimb elements, and pelvic fragments (the latter misidentified as osteoderms)[3]
Comahuesaurus	C. windhauseni	Neuquén Province	"At least three individuals"
Ligabuesaurus[2]	L. leanzai[2]	Neuquén Province[2]	Partial skull and post cranial remains[2]
Rebbachisauridae indet.[2]	unknown[2]	Neuquén Province[2]

Pterosaurs of the Lohan Cura Formation
Genus	Species	Presence	Notes	Images
Ornithocheiriformes indet.[4]	Indeterminate[4]	Neuquén Province[4]	"Isolated teeth"[4]

Turtles of the Lohan Cura Formation
Genus	Species	Presence	Notes	Images

See also

• List of dinosaur-bearing rock formations
• Romualdo Formation