Qigu Formation

Qigu Formation
Qigu Formation
Stratigraphic range: Oxfordian-Early Kimmeridgian, ; 160.8–155.3 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Type	Geological formation
Underlies	Kalaza Formation
Overlies	Toutunhe Formation (Junggar) Qiketai Formation (equivalent unit in the Turpan Basin)
Thickness	Over 520 m (1,710 ft)
Lithology
Primary	Siltstone, sandstone
Location
Coordinates	43°36′N 87°18′E / 43.6°N 87.3°E
Approximate paleocoordinates	42°54′N 97°30′E / 42.9°N 97.5°E
Region	Xinjiang
Country	China
Extent	Southern Junggar Basin (blue); Turpan Basin (disputed) (cyan)
	Qigu Formation (China) Qigu Formation (Dzungaria)

The Qigu Formation is a Late Jurassic (Oxfordian) geologic formation in the Southern Junggar Basin in China. Indeterminate Dinosaur remains are among the fossils that have been recovered from the formation, including the stegosaur ("Angustungui qiketaensis"),^[1] theropod teeth and a fibula.^[2] a stegosaur dorsal vertebra^[3] and a Eusauropod tooth.^[4] Xinjiangtitan was erroneously thought to be from this formation, but it is actually from the older Qiketai Formation, which is in a different basin.^[5] The term "Qigu Formation" is also used to sediments of equivalent age in the Turpan Basin, but this might better be treated as a separate formation. It is laterally equivalent to the Shishugou Formation.

Fossil content

The mass accumulation of Jurassic freshwater turtle fossils belonging to the genus Annemys, discovered in 2009 at a site nicknamed "Mesa Chelonia" in Shanshan County, Xinjiang is thought to likely belong to the Qigu Formation, though it belongs to the strata of the Turpan Basin.^[6]^[7] Remains of indeterminate dinosaurs, including ankylosaurs, metriacanthosaurids, and dromaeosaurids are known from the formation.^[8]^[9]^[10]

The remains of indeterminate rhamphorhynchid pterosaurs have been recovered from the formation. Among others, the following fossils have been found in the formation:^[11]

Crocodyliformes
Taxa	Species	Material	Location	Notes	Images
Nominosuchus	Indeterminate		Liuhuanggou bonebed
Sunosuchus
Theriosuchus

Mammaliamorphs^[12]
Taxa	Species	Material	Location	Notes	Images
Nanolestes	N. mackennai		Liuhuanggou bonebed
Tegotherium	Indeterminate
Dsungarodon	D. zuoi			Docodontan
Sineleutherus	S. uyguricus
Eutriconodonta	Indeterminate

References

^ Ning, Li; Guozhong, Chen; Mateus, Octávio; Tao, Jiang; Yan, Xie; Daqing, Li; Hailu, You; Guangzhao, Peng (2024-10-02). "A new stegosaur (Dinosauria: Ornithischia) from the Upper Jurassic Qigu Formation of Xinjiang, China and a revision on Chinese stegosaurs phylogeny". bioRxiv 10.1101/2024.09.29.615678.
^ Maisch, Michael W.; Matzke, Andreas T. (October 2003). "Theropods (dinosauria, saurischia) from the middle Jurassic Toutunhe Formation of the Southern Junggar Basin, NW China". Paläontologische Zeitschrift. 77 (2): 281–292. Bibcode:2003PalZ...77..281M. doi:10.1007/BF03006942. ISSN 0031-0220. S2CID 129631182.
^ Wings, Oliver; Pfretzschner, Hans-Ulrich; Maisch, Michael W. (2007-01-01). "The first evidence of a stegosaur (Dinosauria, Ornithischia) from the Jurassic of Xinjiang/China". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 243 (1): 113–118. Bibcode:2007NJGPA.243..113W. doi:10.1127/0077-7749/2007/0243-0113. ISSN 0077-7749.
^ Maisch, Michael W.; Matzke, Andreas T. (2019-01-01). "First record of a eusauropod (Dinosauria: Sauropoda) from the Upper Jurassic Qigu-Formation (southern Junggar Basin, China), and a reconsideration of Late Jurassic sauropod diversity in Xinjiang". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 291 (1): 109–117. Bibcode:2019NJGPA.291..109M. doi:10.1127/njgpa/2019/0792. ISSN 0077-7749. S2CID 135213577.
^ Maisch, Michael W.; Matzke, Andreas T. (2019-02-10). "First record of a eusauropod (Dinosauria: Sauropoda) from the Upper Jurassic Qigu-Formation (southern Junggar Basin, China), and a reconsideration of Late Jurassic sauropod diversity in Xinjiang". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 291 (1): 109–117. Bibcode:2019NJGPA.291..109M. doi:10.1127/njgpa/2019/0792. ISSN 0077-7749.
^ Wings, Oliver; Rabi, Márton; Schneider, Jörg W.; Schwermann, Leonie; Sun, Ge; Zhou, Chang-Fu; Joyce, Walter G. (2012), "An enormous Jurassic turtle bone bed from the Turpan Basin of Xinjiang, China", Naturwissenschaften, 114 (11): 925–935, Bibcode:2012NW.....99..925W, doi:10.1007/s00114-012-0974-5, PMID 23086389, S2CID 17423081
^ Gannon, Megan (October 31, 2012), "Jurassic turtle graveyard found in China", Livescience.com
^ Augustin, Felix J.; Matzke, Andreas T.; Maisch, Michael W.; Pfretzschner, Hans-Ulrich (2020-12-15). "A theropod dinosaur feeding site from the Upper Jurassic of the Junggar Basin, NW China". Palaeogeography, Palaeoclimatology, Palaeoecology. 560: 109999. Bibcode:2020PPP...56009999A. doi:10.1016/j.palaeo.2020.109999. ISSN 0031-0182. S2CID 225210438.
^ Augustin, Felix J.; Matzke, Andreas T.; Maisch, Michael W.; Pfretzschner, Hans-Ulrich (July 2020). "First evidence of an ankylosaur (Dinosauria, Ornithischia) from the Jurassic Qigu Formation (Junggar Basin, NW China) and the early fossil record of Ankylosauria". Geobios. 61: S0016699520300504. Bibcode:2020Geobi..61....1A. doi:10.1016/j.geobios.2020.06.005. S2CID 225545154.
^ Maisch, Michael W.; Matzke, Andreas T. (2020-01-01). "Small theropod teeth (Dinosauria) from the Upper Jurassic Qigu Formation of the southern Junggar Basin, NW China". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 295 (1): 91–100. Bibcode:2020NJGPA.295...91M. doi:10.1127/njgpa/2020/0869. S2CID 213709095.
^ Qigu Formation at Fossilworks.org
^ Thomas Martin; Alexander O. Averianov; Hans-Ulrich Pfretzschner (2010). "Mammals from the Late Jurassic Qigu Formation in the Southern Junggar Basin, Xinjiang, Northwest China". Palaeobiodiversity and Palaeoenvironments. 90 (3): 295–319. Bibcode:2010PdPe...90..295M. doi:10.1007/s12549-010-0030-4. S2CID 129008041.