The Río Colorado Subgroup, formerly named as Río Colorado Formation, is a Late Cretaceous (Santonian to Early Campanian) geologic subgroup of the Neuquén Basin in northern Patagonia, Argentina. It belongs to the Neuquén Group and contains the Anacleto and Bajo de la Carpa Formations. The subgroup overlies the Río Neuquén Subgroup and is overlain by the Allen Formation of the Malargüe Group, separated by an unconformity dated to 79 Ma.[1] Dinosaur remains diagnostic to the genus level are among the fossils that have been recovered from the formation.[2]
| Río Colorado Subgroup | |
|---|---|
| Stratigraphic range: Santonian-Early Campanian ~ | |
| Type | Subgroup |
| Unit of | Neuquén Group |
| Sub-units | Anacleto & Bajo de la Carpa Formations |
| Underlies | Malargüe Group Allen Formation |
| Overlies | Río Neuquén Subgroup Plottier Formation |
| Thickness | Up to 240 m (790 ft) |
| Lithology | |
| Primary | Mudstone, sandstone |
| Other | Siltstone, limestone |
| Location | |
| Coordinates | 37°54′S 68°30′W / 37.9°S 68.5°W |
| Approximate paleocoordinates | 40°48′S 53°00′W / 40.8°S 53.0°W |
| Region | Neuquén & Río Negro Provinces |
| Country |  Argentina |
| Extent | Neuquén Basin |
  Río Colorado Subgroup (Argentina) | |
Fossil content edit
Ornithischians edit
| Ornithischians reported from the Río Colorado Subgroup | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Province | Stratigraphic position | Material | Notes | Images |
|
G. cincosaltensis[3] |
Anacleto Formation |
"Skull and postcranial skeleton, postcranial elements, juvenile to subadult."[4] |
 | |||
Sauropods edit
Titanosaur eggs are known from Neuquén Province.[5]
| Sauropods reported from the Río Colorado Subgroup | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Province | Stratigraphic position | Material | Notes | Images |
|
A. wichmannianus[3] |
Anacleto Formation |
 | ||||
|
B.reigi[3] |
Allen Formation | |||||
|
L. scutatus[6] |
||||||
|
M. patagonicus[5] |
Bajo de la Carpa Formation |
Possible synonym of Neuquensaurus | ||||
|
N. australis[7] |
Anacleto Formation | |||||
|
"T." robustus[3] |
Anacleto Formation | |||||
|
T. nanus[7] |
Bajo de la Carpa Formation | |||||
Theropods edit
| Theropods reported from the Río Colorado Subgroup | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Province | Stratigraphic position | Material | Notes | Images |
|
A. comahuaensis[3] |
Anacleto Formation |
"Partial skull."[8] |
     | |||
|
A. calvoi[5] |
Bajo de la Carpa Formation |
"Partial postcranial skeleton."[9] |
||||
|
A. garridoi[5] |
Anacleto Formation |
"Nearly complete skeleton."[8] |
||||
|
N. volans[5] |
Bajo de la Carpa Formation |
"Partial skeleton."[10] |
||||
|
P. deferrariisi[5] |
Bajo de la Carpa Formation |
"Many skeletons."[11] |
||||
|
V. unicus[5] |
Bajo de la Carpa Formation |
"Partial hind limb."[8] |
||||
See also edit
References edit
- ^ Leanza et al., 2004, p.63
- ^ Weishampel et al., 2004, pp. 603-604
- ^ a b c d e f g h i j k l m n o p q "63.10 Provincia de Río Negro, Argentina; 4. Río Colorado Formation," in Weishampel, et al. (2004). Page 604.
- ^ "Table 18.1," in Weishampel, et al. (2004). Page 395.
- ^ a b c d e f g h i j k l m n o p q r s t u v "63.6 Provincia de Neuquén, Argentina; 3. Río Colorado Formation," in Weishampel, et al. (2004). Page 603.
- ^ a b Listed as "?Loricosaurus scutatus" in "63.6 Provincia de Neuquén, Argentina; 3. Río Colorado Formation" and "63.10 Provincia de Río Negro, Argentina; 4. Río Colorado Formation," in Weishampel, et al. (2004). Pages 603-604.
- ^ a b c d "63.6 Provincia de Neuquén, Argentina; 3. Río Colorado Formation" and "63.10 Provincia de Río Negro, Argentina; 4. Río Colorado Formation," in Weishampel, et al. (2004). Pages 603-604.
- ^ a b c "Table 3.1," in Weishampel, et al. (2004). Page 49.
- ^ "Table 11.1," in Weishampel, et al. (2004). Page 211.
- ^ "Table 11.1," in Weishampel, et al. (2004). Page 213.
- ^ "Table 11.1," in Weishampel, et al. (2004). Page 212.
Bibliography edit
- Leanza, H.A.; S. Apesteguia; F.E. Novas, and M.S. De la Fuente. 2004. Cretaceous terrestrial beds from the Neuquén Basin (Argentina) and their tetrapod assemblages. Cretaceous Research 25. 61–87. Accessed 2019-02-16.
- Weishampel, David B.; Peter Dodson, and Halszka (eds.) Osmólska. 2004. The Dinosauria, 2nd edition, 1–880. Berkeley: University of California Press. Accessed 2019-02-21.ISBN 0-520-24209-2