Nanlinghu Fm
Type Locality and Naming
The named section is located in Nanling Lake, Tongling District, Anhui Province. Upper-middle formation in Qinglong Gr. [See Additional Information for nomenclature details.]
Synonym:
Lithology and Thickness
It is composed of carbonate rocks, and can be divided into two parts from bottom to top. Upper part is thin to medium thick limestone, and the bottom is generally interbedded with purplish red or yellow green nodular limestone. Upper part is mainly composed of medium-thick caesian dense limestone with a thin layer of crumpled limestone. It has worm-like structure and developed suture lines. At the bottom, nodular limestone rich in ammonoids, such as Tirolites, first appears as the bottom boundary, and at the top, vermicular limestone or limestone under dolomite is the top boundary. Thickness 160 to 645 m.
Relationships and Distribution
Lower contact
It has a concordant contact with the underlying Helongshan Fm
Upper contact
It has a concordant contact with the overlying Dongma'anshan Fm (Zhoucongcun Fm).
Regional extent
Distributed in the Lower Yangtze area
GeoJSON
Fossils
Abundant production of ammonoids, bivalves and conodonts. In the lower and upper segments, ammonoid Tirolites columbites zone and Subcolumbites zone can be constructed respectively. Two conodont assemblages can be constructed from bottom to top: (1) Neospathodus collinsoni assemblage; (2) Neospathodus anhuiensis- N. homeri assemblage; In addition, still produce ichthyosaur and fish fossils
Age
Depositional setting
Shallow marine facies
Additional Information
Synonym:
Lithology and Thickness:
It is composed of carbonate rocks, and can be divided into two parts from bottom to top. Upper part is thin to medium thick limestone, and the bottom is generally interbedded with purplish red or yellow green nodular limestone. Upper part is mainly composed of medium-thick caesian dense limestone with a thin layer of crumpled limestone. It has worm-like structure and developed suture lines. At the bottom, nodular limestone rich in ammonoids, such as Tirolites, first appears as the bottom boundary, and at the top, vermicular limestone or limestone under dolomite is the top boundary. Thickness 160 to 645 m.
Lithology-pattern: Limestone
Relationships and Distribution:
Lower contact:
It has a concordant contact with the underlying Helongshan Fm
Upper contact:
It has a concordant contact with the overlying Dongma'anshan Fm (Zhoucongcun Fm).
Regional extent:
Distributed in the Lower Yangtze area
GeoJSON:
Fossils:
Abundant production of ammonoids, bivalves and conodonts. In the lower and upper segments, ammonoid Tirolites columbites zone and Subcolumbites zone can be constructed respectively. Two conodont assemblages can be constructed from bottom to top: (1) Neospathodus collinsoni assemblage; (2) Neospathodus anhuiensis- N. homeri assemblage; In addition, still produce ichthyosaur and fish fossils
Age:
The age was defined as the late Olenekian of the Early Triassic
Age span:
Beginning stage: Olenekian
Fraction up in beginning stage: 0.6
Beginning date (Ma):
Ending stage: Olenekian
Fraction up in ending stage: 1.0
Ending date (Ma):
Depositional setting:
Shallow marine facies
Depositional-pattern:
Additional Information
The former Nanlinghu Fm is a set of shallow marine limestone strata distributed in Tongling area, Anhui Province, between the Tashan Fm of the Lower Triassic (Helongshan Fm of this lexicon) and the Fenling Fm of the Middle Triassic, which is dated as the Anisian of the Middle Triassic. Wang Guixiang (1984) dated the group to the late Early Triassic Olenekian. In 1982, Anhui Bureau of Geology and Mineral Resources proposed to abandon the Early Triassic "Biandanshan Fm ", which was renamed Nanlinghu Fm by Guo Peixia and Xu Jiacong (1978). Chen Huacheng et al. (1989) merged the named Nanlinghu Fm with the overlaying "watershed formation" and collectively referred to it as the Nanlinghu Fm. The age was defined as the late Olenekian of the Early Triassic, and the latter meaning was used in this lexicon.