Qigu Formation

{{Short description|Geological formation in Xinjiang, China}}

{{Infobox rockunit

| name = Qigu Formation

| image =

| caption =

| type = Geological formation

| age = Oxfordian-Early Kimmeridgian,
{{fossilrange|160.8|155.3}}

| period = Oxfordian

| prilithology = Siltstone, sandstone

| otherlithology =

| namedfor =

| namedby =

| region = Xinjiang

| country = China

| coordinates = {{coord|43.6|N|87.3|E|display=inline,title}}

| paleocoordinates = {{coord|42.9|N|97.5|E|display=inline}}

| unitof =

| subunits =

| underlies = Kalaza Formation

| overlies = Toutunhe Formation (Junggar) Qiketai Formation (equivalent unit in the Turpan Basin)

| thickness = Over {{convert|520|m|abbr=on}}

| extent = Southern Junggar Basin (blue)
 Turpan Basin (disputed) (cyan)

| area =

| map = {{Location map+ | China Xinjiang Northern

| relief = 1

| width = 250

| float = center

| places =

{{Location map~ | China Xinjiang Northern

| lat_deg = 45.6

| lon_deg = 85.0

| mark = Blue pog.svg

| marksize = 8

}}

{{Location map~ | China Xinjiang Northern

| lat_deg = 43.0

| lon_deg = 90.5

| mark = Cyan pog.svg

| marksize = 10

}}

{{Location map~ | China Xinjiang Northern

| lat_deg = 43.8

| lon_deg = 87.5

| mark = Blue pog.svg

| marksize = 8

}}

}}

| map_caption =

}}

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"),{{Cite bioRxiv |last1=Ning |first1=Li |last2=Guozhong |first2=Chen |last3=Mateus |first3=Octávio |last4=Tao |first4=Jiang |last5=Yan |first5=Xie |last6=Daqing |first6=Li |last7=Hailu |first7=You |last8=Guangzhao |first8=Peng |date=2024-10-02 |title=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 }} theropod teeth and a fibula.{{Cite journal|last1=Maisch|first1=Michael W.|last2=Matzke|first2=Andreas T.|date=October 2003|title=Theropods (dinosauria, saurischia) from the middle Jurassic Toutunhe Formation of the Southern Junggar Basin, NW China|journal=Paläontologische Zeitschrift|volume=77|issue=2|pages=281–292|doi=10.1007/BF03006942|bibcode=2003PalZ...77..281M |s2cid=129631182|issn=0031-0220}} a stegosaur dorsal vertebra{{Cite journal|last1=Wings|first1=Oliver|last2=Pfretzschner|first2=Hans-Ulrich|last3=Maisch|first3=Michael W.|date=2007-01-01|title=The first evidence of a stegosaur (Dinosauria, Ornithischia) from the Jurassic of Xinjiang/China|journal=Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen|volume=243|issue=1|pages=113–118|doi=10.1127/0077-7749/2007/0243-0113|bibcode=2007NJGPA.243..113W |issn=0077-7749}} and a Eusauropod tooth.{{Cite journal|last1=Maisch|first1=Michael W.|last2=Matzke|first2=Andreas T.|date=2019-01-01|title=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|url=https://www.researchgate.net/publication/330758512|journal=Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen|volume=291|issue=1|pages=109–117|doi=10.1127/njgpa/2019/0792|bibcode=2019NJGPA.291..109M |s2cid=135213577 |issn=0077-7749}} Xinjiangtitan was erroneously thought to be from this formation, but it is actually from the older Qiketai Formation, which is in a different basin.{{Cite journal |last1=Maisch |first1=Michael W. |last2=Matzke |first2=Andreas T. |date=2019-02-10 |title=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 |url=http://www.schweizerbart.de/papers/njgpa/detail/291/90381/First_record_of_a_eusauropod_Dinosauria_Sauropoda_?af=crossref |journal=Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen |language=en |volume=291 |issue=1 |pages=109–117 |doi=10.1127/njgpa/2019/0792 |bibcode=2019NJGPA.291..109M |issn=0077-7749}} 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.