Javelina Formation
Javelina Formation Stratigraphic range: Maastrichtian, 70–66.5 Ma | |
---|---|
Type | Geological formation |
Underlies | Black Peaks Formation |
Overlies | Aguja Formation |
Location | |
Region | North America |
Country | USA, Texas |
The Javelina Formation is a geological formation in Texas. Dating has shown that the strata date to the Maastrichtian stage of the Late Cretaceous, approximately 70 to 66.5 million years old.[1] The middle part of the formation has been dated to about 69 million years ago plus or minus 1 Ma and the top situated near the Cretaceous–Paleogene boundary (in the overlying Black Peaks Formation[1]), dated to 66 Ma ago.[2] Dinosaur remains are among the fossils that have been recovered from the formation.[3]
Age
The exact age range of the Javelina Formation has been difficult to determine.[4] Only one geological site in the Javelina Formation has thus far yielded the correct rock types for radiometric dating. The outcrop, situated in the middle strata of the formation about 90 meters below the K-Pg boundary and within the local range of Alamosaurus fossils and below two sites that have yielded Quetzalcoatlus fossils, was dated to 69.0 plus or minus 0.9 million years old in 2010.[2]
Vertebrate paleofauna
- Alamosaurus sanjuanensis
- Bravoceratops polyphemus
- cf. Edmontosaurus sp.
- Quetzalcoatlus northropi
- cf. Torosaurus utahensis[5]
- cf. Troodon sp.
- cf. Tyrannosaurus rex
It also contains the rays Rhombodus and Dasyatis.[6]
Plants
- Javelinoxylon[7]
See also
References
- 1 2 Woodward, H. N. (2005). Bone histology of the sauropod dinosaur Alamosaurus sanjuanensis from the Javelina Formation, Big Bend National Park, Texas.
- 1 2 Lehman, T.M., McDowell, F. and J. Connelly, J. (2006). "First isotopic (U-Pb) age for the Late Cretaceous Alamosaurus vertebrate fauna of West Texas, and its significance as a link between two faunal provinces." Journal of Vertebrate Paleontology, 26: 922–928.
- ↑ Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, North America)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 574-588. ISBN 0-520-24209-2.
- ↑ Sullivan, R.M., and Lucas, S.G. 2006. "The Kirtlandian land-vertebrate "age" – faunal composition, temporal position and biostratigraphic correlation in the nonmarine Upper Cretaceous of western North America." New Mexico Museum of Natural History and Science, Bulletin 35:7-29.
- ↑ Hunt, ReBecca K. and Thomas M. Lehman. 2008. Attributes of the ceratopsian dinosaur Torosaurus, and new material from the Javelina Formation (Maastrichtian) of Texas. Journal of Paleontology 82(6): 1127-1138.
- ↑ Hunt, ReBecca K., Vincent L. Santucci and Jason Kenworthy. 2006. "A preliminary inventory of fossil fish from National Park Service units." in S.G. Lucas, J.A. Spielmann, P.M. Hester, J.P. Kenworthy, and V.L. Santucci (ed.s), Fossils from Federal Lands. New Mexico Museum of Natural History and Science Bulletin 34, pp. 63-69.
- ↑ Jacobs, L. 1995. Lone Star Dinosaurs. Texas A&M University Press. p.102