Hanson Formation

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Hanson Formation
Stratigraphic range: Early Jurassic
Type Geological formation
Underlies Prebble Formation
Overlies Falla Formation
Location
Region Mount Kirkpatrick, Antarctic

The Hanson Formation is one of only two major dinosaur-bearing rock formations found on the continent of Antarctica to date; the other is the Santa Marta Formation from the Late Cretaceous. The formation has yielded only a handful of Mesozoic specimens so far and most of it is as yet unexcavated. Part of the Victoria Group of the Transantarctic Mountains, it is below the Prebble Formation and above the Falla Formation.[1]

Fauna[edit]

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.

Fauna[edit]

Dinosaurs[edit]

[2]

Dinosaurs of the Hanson Formation
Taxa Presence Description Images

Suborder:

  1. Cryolophosaurus[2]
  1. Stratigraphically present in the Hanson Formation.[2]

"Partial skull and partial postcranium."[3]

Infraorder:

  1. Glacialisaurus[4]
  1. Stratigraphically present in the Hanson Formation.[4]

Suborder:

  1. Indeterminate remains.
  1. Stratigraphically present in the Hanson Formation.[2]


See also[edit]

References[edit]

  1. ^ Elliot, D.H. (1996). The Hanson Formation: a new stratigraphical unit in the Transantarctic Mountains, Antarctica. Antarctic Science 8(4):389-394.[1]
  2. ^ 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.
  3. ^ "Table 4.1," in Weishampel, et al. (2004). Page 74.
  4. ^ a b Smith, Nathan D.; 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.