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Lark Quarry Dinosaur Trackways (also known just as Lark Quarry) in Australia was once considered to be the site of the world's only known record of a dinosaur stampede,〔http://www.derm.qld.gov.au/parks/lark-quarry/index.html Queensland Parks and Widelife Service: Lark Quarry Conservation Park〕 with fossilised footprints having been originally interpreted as a predator stalking and causing a stampede of around 150 two-legged dinosaurs. This interpretation has been challenged in recent years, with evidence suggesting it may have been a natural river crossing.〔http://theconversation.com/no-dinosaur-stampede-at-lark-quarry-so-what-really-happened-28971 The Conversation No dinosaur stampede at Lark Quarry – so what really happened?〕 The Lark Quarry site is about south west of the western Queensland town of Winton. ==Origin== The traditional account is that a group of perhaps 180 chicken-sized Coelurosaurs (''Skartopus'') and Bantam to emu-sized ''Wintonopus'' were disturbed by the arrival of a single much larger carnivore - a theropod named ''Australovenator'', which may have been up to 6 metres long with 50-centimetre feet. ''Skartopus'' and ''Wintonopus'' are thought to have stampeded past ''Australovenator'', leaving thousands of footprints in the surrounding mudflat.〔(Australian National Heritage list: Department of the Environment, Water, Heritage and the Arts )〕 More recent research〔Anthony Romilio, Steven W. Salisbury, A reassessment of large theropod dinosaur tracks from the mid-Cretaceous (late Albian-Cenomanian) Winton Formation of Lark Quarry, central-western Queensland, Australia: A case for mistaken identity, ''Cretaceous Research'', In Press, Corrected Proof, Available online 22 November 2010, ISSN 0195-6671, .〕 by the University of Queensland however has shown that the large tracks apparently didn't belong to a large theropod at all, but were probably left by a large herbivore similar to ''Muttaburrasaurus''.〔(Australia’s biggest carnivorous dinosaur forced to take a walk ) UQ News, 16 December 2010〕 Additional research by Romilio ''et al.'' published in the Journal of Vertebrate Paleontology in 2013 casts further doubt on the original interpretation. Analysis of the sediments indicates that they were deposited by a seasonal water course with water flowing at different depths and speeds at different times. The footprints were most likely made over a period of time, perhaps several days, by dinosaurs crossing the channel. The authors also found no significant difference in the form of the footprints attributed to both ''Skartopus'' and ''Wintonopus'', and suggest that they were made by different-sized animals of the same species. Whatever actually took place, not long after the incident, the water level began to rise, covering the tracks with sandy sediments before the mud had dried. The footprints were buried beneath sand and mud as the water levels continued to rise and fall. Over thousands of millennia, the rich river plain with sandy channels, swamps and lush lowland forest dried up. The sediment covering the footprints was compressed to form rock. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Lark Quarry Dinosaur Trackways」の詳細全文を読む スポンサード リンク
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