Mount Kirkpatrick Formation

Cryolophosaurus - One of the dinosaurs that was discovered in the Hanson layer of the Mt. Kirkpatrick Formation.

Mount Kirkpatrick Formation
Type	Geological formation
Location
Region	Mount Kirkpatrick, Antarctic

The Mount Kirkpatrick Formation is one of only two major dinosaur-bearing rock formations yet found on the continent of Antarctica; the other is the Santa Marta Formation from the Late Cretaceous. However, only a handful of prehistoric specimens have been found in the formation, and large portions of it are yet to be excavated.

Presently the Mount Kirkpatrick Formation sits about 700 kilometres from the South Pole, yet when it was formed, it was part of the super continent Gondwanaland and much further north. Scientists add that the formation was once a river bed, suggesting why dinosaur finds have been discovered in the area. Now however, the area is raised up 14,000 feet on Mount Kirkpatrick. Because of this height, expeditions to the formation are increasingly difficult and results are seldom.

Stratigraphy

The Mount Kirkpatrick Formation comprises numerous layer formations; the uppermost layer is the Prebble Formation, followed by the Hanson Formation in which most dinosaur finds have been made. Below that is the Triassic Falla Formation and finally the Fremouw Formation which lies on top of the mountain's core. Other than the uppermost layers of the mountain, the rest are even less examined.

The several layers of the Mount Kirkpatrick Formation are all made of different rock. The very top layer of Mount Kirkpatrick is consisted of basalt. Whilst the Hanson Formation is made primarily of sandstone, the other layers are made of either volcanic deposits or ganister. It was not until 1996 that many of the mountain's layers were truly defined, with the Hanson Formation being created, as well as the Falla Formation being redefined.

Fauna

Most finds on the formation have been discovered in the second layer, the Hanson Formation. The first dinosaur to be discovered from the Hanson Formation was the predator Cryolophosaurus in 1991, which was then formally described in 1994. Alongside these dinosaur remains were fossilized trees, suggesting that plant matter had once grown on Antarctica's surface before it drifted southward. Other finds from the formation include tritylodonts, hebivorous mammal-like reptiles and crow-sized pterosaurs. Surprisingly were the discovery of prosauropod remains, which were found commonly on other continents only until the Early Jurassic. However, the bone fragments found at the Hanson Formation were dated until the Middle Jurassic, millions of years later. In 2004, paleontologists discovered partial remains of a large sauropod dinosaur that has not formally been described yet.

Dinosaurs

^[1]

Dinosaurs of the Hanson Formation
Taxa	Presence	Description	Images
Superfamily: Allosauroidea[1] Cryolophosaurus[1]	Stratigraphically present in the Hanson Formation.[1]	"Partial skull and partial postcranium."[2]	Cryolophosaurus
Infraorder: Prosauropoda Glacialisaurus[3]	Stratigraphically present in the Hanson Formation.[3]
Suborder: Theropoda Indeterminate remains.	Stratigraphically present in the Hanson Formation.[1]

See also

• List of dinosaur-bearing rock formations

References

1. ^ ^{a b c d e} Weishampel, David B; et al. (2004). "Dinosaur distribution (Early Jurassic, Asia)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. p.537. ISBN 0-520-24209-2.
2. ^ "Table 4.1," in Weishampel, et al. (2004). Page 74.
3. ^ ^{a b} Smith, Nathan D.; and Pol, Diego (2007). "Anatomy of a basal sauropodomorph dinosaur from the Early Jurassic Hanson Formation of Antarctica" (pdf). Acta Palaeontologica Polonica 52 (4): 657–674. http://www.app.pan.pl/acta52/app52-657.pdf. 

• Elliot, D.H. (1996). The Hanson Formation: a new stratigraphical unit in the Transantarctic Mountains, Antarctica. Antarctic Science 8(4):389-394.[1]

External links

• Findings from the Mount Kirkpatrick Formation