Fentou Fm
Type Locality and Naming
It was named by Pan Jiang (1965). The type section is near the Fentou Village, Tangshan in Jiangning County, 25 km east of the Nanjing City seat, Jiangsu Province. The Zhaishan Fm, proposed by the Anhui 321st Geological Party at Zhaishan of Anhui Province in 1969, is more properly assigned to the upper part of the Fentou Fm because of their similar lithology and fossils.
Synonym: (坟头组)
Lithology and Thickness
The formation, 214 m thick at the type section, is subdivided into three parts. Lower and Middle parts are composed of grey green fine-gained quartzose sandstone intercalated with pelitic siltstone and yield fish fossil Sinacanthus and minor trilobite encrinurids. Upper part consists of grey yellow or grey green pelitic siltstone, silty mudstone intercalated with fine-grained quartzose sandstone and yellow green shale. The top consists of grey green, yellow pelitic siltstone.
Relationships and Distribution
Lower contact
It is conformably contacted with the underlying Houjiatang Fm
Upper contact
It is conformably contacted with the overlying Maoshan Fm
Regional extent
The exposures are observed in some places of south Jiangsu and south Anhui Provinces.
GeoJSON
Fossils
The shale yields trilobite Coronocephalus, Latiproetus; brachiopod Striispirifer, Salopinella; bivalves Orthonota, Praectenodonta, Modiomorpha, Modiolopsis; gastropods Trochonema, Rotellomphalus, Hormotoma; cephalopods Sichuanoceras, Protobactrites and fish Sinacanthus, Kiangsuaspis. The top pelitic siltstone bears brachiopod Lingula; chitinozoa Angochitina longicollis; bivalve Orthonota perlata; and gastropods Umbonellina, Rotellomphalus, Seelya, Lophospira , etc.
Age
Depositional setting
The deposition characters and fossils of the formation indicate nearshore shallow water to extreme shallow water.
Additional Information