The Río Colorado Subgroup, formerly named as Río Colorado Formation, is a
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...
(
Santonian
The Santonian is an age in the geologic timescale or a chronostratigraphic stage. It is a subdivision of the Late Cretaceous Epoch or Upper Cretaceous Series. It spans the time between 86.3 ± 0.7 mya ( million years ago) and 83.6 ± 0.7 m ...
to
Early Campanian) geologic
subgroup
In group theory, a branch of mathematics, a subset of a group G is a subgroup of G if the members of that subset form a group with respect to the group operation in G.
Formally, given a group (mathematics), group under a binary operation  ...
of the
Neuquén Basin
Neuquén Basin () is a sedimentary basin covering most of Neuquén Province in Argentina. The basin originated in the Jurassic and developed through alternating continental and marine conditions well into the Tertiary. The basin bounds to the wes ...
in northern
Patagonia
Patagonia () is a geographical region that includes parts of Argentina and Chile at the southern end of South America. The region includes the southern section of the Andes mountain chain with lakes, fjords, temperate rainforests, and glaciers ...
, Argentina. It belongs to the
Neuquén Group
The Neuquén Group is a geologic unit, group of geologic formations found in Argentina. Rocks in the Neuquén Group fall within the Cenomanian to early Campanian stages of the Late Cretaceous Period. It overlies the older Lohan Cura Formation and ...
and contains the
Anacleto and
Bajo de la Carpa Formation
The Bajo de la Carpa Formation is a geologic formation of the Neuquén Basin that outcrop, crops out in northern Patagonia, in the provinces of Río Negro Province, Río Negro and Neuquén Province, Neuquén, Argentina. It is the oldest of two for ...
s. The subgroup overlies the
Río Neuquén Subgroup
The Río Neuquén Subgroup is a geological subgroup in the Neuquén Basin, Neuquén Province, Argentina, whose strata date back to the Late Cretaceous. The subgroup, formerly defined as a formation, is the middle unit of the Neuquén Group and co ...
and is overlain by the
Allen Formation
The Allen Formation is a geological formation in Argentina whose strata date back to the Late Cretaceous (middle Campanian to early Maastrichtian.Salgado et al., 2007 Dinosaur remains are among the fossils that have been recovered from the forma ...
of the
Malargüe Group
The Malargüe Group is a group of geologic formations of the Neuquén Basin of the Mendoza, Neuquén, Río Negro and La Pampa Provinces in northern Patagonia, Argentina. The formations of the Malargüe Group range in age between the middle Campa ...
, separated by an
unconformity
An unconformity is a buried erosional or non-depositional surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous. In general, the older layer was exposed to erosion for an interval ...
dated to 79 Ma.
[Leanza et al., 2004, p.63] Dinosaur
Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic Geological period, period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the #Evolutio ...
remains diagnostic to the
genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
level are among the fossils that have been recovered from the formation.
[Weishampel et al., 2004, pp. 603-604]
Fossil content
Ornithischians
Sauropods
Titanosaur eggs are known from Neuquén Province.
["63.6 Provincia de Neuquén, Argentina; 3. Río Colorado Formation," in Weishampel, et al. (2004). Page 603.]
Theropods
See also
*
List of stratigraphic units with dinosaur body fossils
This is a list of stratigraphic units from which dinosaur body fossils have been recovered. Although Dinosauria is a clade which includes modern birds, this article covers only Mesozoic stratigraphic units. Units listed are all either formation ra ...
*
List of stratigraphic units with dinosaur trace fossils
This is a list of stratigraphic units dinosaur trace fossils have been recovered from. Although Dinosauria is a clade which includes the descendant taxon Aves (modern birds), this article covers only stratigraphic units containing Mesozoic forms. ...
References
Bibliography
*
* {{citation , last1=Weishampel , first1=David B. , last2=Dodson , first2=Peter , last3=Osmólska , first3=Halszka , year=2004 , title=The Dinosauria, 2nd edition , url=https://books.google.com/books?id=vtZFDb_iw40C , publisher=Berkeley: University of California Press , pages=1–880 , accessdate=2019-02-21 , isbn=0-520-24209-2
Geologic formations of Argentina
Neuquén Group
Upper Cretaceous Series of South America
Cretaceous Argentina
Campanian Stage
Santonian Stage
Mudstone groups
Sandstone groups
Fossiliferous stratigraphic units of South America
Paleontology in Argentina
Geology of Neuquén Province
Geology of Río Negro Province