Yangliujing Formation

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Yangliujing Formation
Stratigraphic range: late Anisian-Ladinian
246–242  Ma
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Type Geological formation
Underlies Zhuganpo Formation
Overlies Guanling Formation
Lithology
Primary Dolomite
Other Limestone
Location
Coordinates 25°54′N105°30′E / 25.9°N 105.5°E / 25.9; 105.5
Approximate paleocoordinates 12°18′N94°30′E / 12.3°N 94.5°E / 12.3; 94.5
Region Guizhou & Yunnan Provinces
CountryFlag of the People's Republic of China.svg  China
Extent Yunnan–Guizhou Plateau
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Pink ff0080 pog.svg
Yangliujing Formation (China)
China Guizhou location map.jpg
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Yangliujing Formation (Guizhou)

The Yangliujing Formation is a Middle Triassic geologic unit found in the Guizhou and Yunnan Provinces of southern China.

Contents

Description

Most of the formation is represented by massive dolomites, indicative of a shallow-water depositional environment. Fossils are generally rare, but conodonts from the Anisian-Ladinian boundary (namely several species of Neogondolella ) are known from the lower part of the formation. Some marine reptiles have been found in dolomitic limestone near Dingxiao, an area of Guizhou sometimes considered to preserve the upper part of the Yangliujing Formation. However, under a more restrictive definition of the Yangliujing Formation, the fossils of Dingxiao would instead belong to the overlying Zhuganpo Formation. [1] [2]

Fossil content

The following fossils have been reported from the formation:

Fish
Brachiopods
Bivalves
Crinoids
Conodonts

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References

  1. Benton et al., 2013
  2. Sun et al., 2016

Bibliography