Lishan Fm
Type Locality and Naming
It was named by Wang Hengsheng, Li Chunyu as the “Lishan Coal Series” in 1930. The naming section is located in the Lishan Coal Mine, Jian’ou County, Fujian Province, with its reference section being situated at Gaoming Pit, Zhangping County (ca. 25.3°N, 117.4°E).
Synonym: （梨山组）
Lithology and Thickness
Lower member is composed of grey, grey-black thick-bedded medium-, and coarse-grained quartz-sandstones and conglomerates, with its upper part being intercalated with thin-bedded siltstones and fine-grained sandstones, and with its basal part being always possessed of a layer of pebble-bearing gritstones, with a thickness of 450 m. Upper member consists of grey-black thick-bedded and massive siltstones, intercalated with a good many of thin-bedded coal layers or coal seams and constituting an alternating layer together with medium-grained quartz-sandstones, with a thickness of about 500 m.
Relationships and Distribution
Lower contact
The basal part of the formation is in a conformable or parallel unconformable contact with the underlying upper Triassic Jiaokeng Fm or Wenbin Fm. Sometimes it overlies still older strata.
Upper contact
Regionally, the schematic strat column indicates the next younger unit as Zhangping Fm
Regional extent
The formation is distributed in the areas of Chong’an, Shaowu, Jiangle, Qingliu, Changding, Pucheng, Jianou, Nanping, Longxi, Datian, Zhangping, Hua’an and Nanjing Counties. Its lithology and rock facies are relatively consistent, containing 2-21 coal layers, with 2-5 mineable coal beds being encountered in the areas of Gexian of Cheng’an County, Houtang of Jianyang County, Long’an of Taining County and Daheng of Naping County. Coeval with the Xiacun Fm and Pankeng Fm in this same region.
GeoJSON
Fossils
The fossils encountered in the lower member of the formation includes spinicaudatans as represented by the Palaeolimadia hojiensis-Euestheria shandanensis assemblage; plant fossils such as Thaumatopteris sp., Dictyophyllum sp., Todites sp. and Phoenicopsis sp. The upper member of it yields bivalves such as Sibireconcha jenisejensis, Pseudocardinia elliptica and P. elongatiformis; and plant fossils as represented by Coniopteris hymenophylloides, Cladophylebis shansiensis, Phoenicopsis angustifolia, Czekanowskia rigida and Sagenopteris sp.
Age
Depositional setting
The formation belongs to fluvial-lacustrine and swamp-facies deposits.
Additional Information