Qinglong Gr
Type Locality and Naming
Named Qinglong Limestone, the term refers to a set of thin-bedded limestone formations above the Permian Longtan Coal Measures in Jiangsu and Zhejiang, dating from the Permian-Triassic. In 1932, Li Siguang and Zhu Sen first corrected it to the Triassic period, but there was no fossil evidence. Li Yuyao in 1935, such as found in the limestone "Qinglong" early Triassic fossils, 1936-1937 meter ronson, etc to redefine "qinglong limestone", for the horizon between Permian "longtan" or "changxing limestone", "yellow kico lines" (including "fan home pond coal measures"), mainly limestone, the top of the limestone breccia a stratum, age of early Triassic, Xu Hankui, etc in 1959, 1960 Chen Chuzhen successively in "qinglong limestone" found in Triassic ammonoids and bivalve fossil. In 1962, Zhao Jinke and others renamed it Qinglong Group and divided it into upper and lower parts, which belonged to the Middle and Lower Triassic respectively. Now divided into four formations from bottom to top: Yinkeng Fm, Herongshan Fm, Nanlinghu Fm and Dongma'anshan Fm. See Additional Information for history of divisions; and see entries for those individual formations for type sections.
Synonym:
Lithology and Thickness
Currently divided into four formations from bottom to top: Yinkeng Fm (marl), Herongshan Fm (clayey limestone), Nanlinghu Fm (nodular to dense limestone) and Dongma'anshan Fm (dolomite). See the individual formation for lithologic details.
Relationships and Distribution
Lower contact
The bottom boundary is marked by the appearance of yellow-green clay layer several centimeters thick, which is conformable with the underlying Upper Permian Changxing or Dalong Fm
Upper contact
At the top, dolomites are in integrated contact with the overlying Middle Triassic Huangmaqing Fm
Regional extent
Distributed in the Lower Yangtze area
GeoJSON
Fossils
See the individual formation for details.
Age
Depositional setting
See the individual formation for details.
Additional Information
Synonym:
Lithology and Thickness:
Currently divided into four formations from bottom to top: Yinkeng Fm (marl), Herongshan Fm (clayey limestone), Nanlinghu Fm (nodular to dense limestone) and Dongma'anshan Fm (dolomite). See the individual formation for lithologic details.
Lithology-pattern: Dolomitic limestone
Relationships and Distribution:
Lower contact:
The bottom boundary is marked by the appearance of yellow-green clay layer several centimeters thick, which is conformable with the underlying Upper Permian Changxing or Dalong Fm
Upper contact:
At the top, dolomites are in integrated contact with the overlying Middle Triassic Huangmaqing Fm
Regional extent:
Distributed in the Lower Yangtze area
GeoJSON:
Fossils:
See the individual formation for details.
Age:
Early Triassic and Anisian on schematic stratigraphic column.
Age span:
Beginning stage: Induan
Fraction up in beginning stage: 0.0
Beginning date (Ma):
Ending stage: Anisian
Fraction up in ending stage: 1.0
Ending date (Ma):
Depositional setting:
See the individual formation for details.
Depositional-pattern:
Additional Information
Since 1962, there have been many different opinions on the further division of Qinglong Gr and the lithostratigraphic circle. (1) The lithostratigraphic range of "Qinglong Limestone" determined by Ji Rongsen et al. (1936~1937) should be maintained. A. In 1965, the Qinglong Gr was divided into Yinkeng Fm, Helongshan Fm, Wutian Fm and Wuzhishan Fm by the Guichi Stratigraphic Research Team in Anhui Province from bottom to top; B. In 1966, Gong Yichang et al. divided Qinglong Gr in Tongling area into Xiaolingting Fm, Tashan Fm, Nanlinghu Fm, Fengling Fm and Longtoushan Fm from bottom to top; C. In 1970, the Qinglong Group in Jiangsu was divided into Lower Qinglong Group and Upper Qinglong Group by the Jiangsu Regional Survey Team; D. In 1992, Wang Zunzhou et al. divided the Qinglong Group in the Lower Yangtze area into the Yinkeng Fm, He Longshan Fm, Nanlinghu Fm and East Ma'anshan Fm from bottom to top. (2) The lithostratigraphic range of "Qinglong Limestone" as determined by Ji Rongsen et al. (1936~1937) is reduced, excluding the "lime breccia" (i. e. salt-soluble breccia) at the top. A. In 1980, Guo Peixia et al. divided the Qinglong Gr in Anhui into Yinkeng Fm, Helongshan Fm and Biandanshan Fm from bottom to top; B. In 1982, Min Qingkui et al. divided the Qinglong Gr in Nanjing area into Qinglong Fm (narrow sense), Hushan Fm and Cangbomen Fm from bottom to top; C. In 1984, Jiangsu Bureau of Geology and Mineral Resources divided the Yulong Group into the Lower Qinglong Gr and the Upper Qinglong Gr. This lexicon maintains the lithostratigraphic range of "Qinglongyou Limestone" as determined by Ji Rongsen et al. (1936~1937), which can be divided into four formations from bottom to top: Yinkeng Fm, Herongshan Fm, Nanlinghu Fm and Dongma'anshan Fm.