Majian Fm
Type Locality and Naming
It was named by Regional Survey Party of Zhejiang Province in 1963. The naming section is located in the vicinity of an animal farm northeast of the Majian Township, Lianxi County, Zhejiang Province.
Synonym: （马涧组）
Lithology and Thickness
Lower part is composed of grey-white pebble-bearing quartz-sandstones, yellow-green siltstones and grey-black silty mudstones, intercalated with carbonaceous shales and coal seams, with a thickness of 98 m. Upper part is composed of grey-yellow conglomerates, pebble-bearing sandstones and grey-white, grey-violet and yellow-green medium-, and fine-grained sandstones, grey-black carbonaceous siltstones, silty mudstones and carbonaceous shales, intercalated with coal seams, with a thickness of about 247 m.
Relationships and Distribution
Lower contact
Its basal part is in an unconformable contact with the underlying Chishanwu Fm or Carboniferous System.
Upper contact
Regionally, the schematic strat column indicates the next younger unit as Yushanjian Fm
Regional extent
The formation is distributed mainly in the Majian, Ganxi and Boshe areas of Lanxi County. In addition, there occur exposures of the formation also in Linqi area of Chunan County, Pingyue and Hualong areas of Linan County. The lithology of the formation is greatly changeable in various regions. As in the Linqi area the present formation represents an alternating layer of purple massive conglomerates, intercalated with fine-grained sandstones, medium-, and thick-bedded fine-grained sandstones and siltstones, intercalated with carbonaceous shales and lenticular coal beds, with a thickness of about 1089 m, yielding abundant plant fossils. In the Changxing region the analogous deposits are known as the “Xiangshan Formation”.
GeoJSON
Fossils
It yields bivalves as represented by the Ferganoconcha- Tutuella-Pseudocardinia assemblage; plant fossils as represented by the Todites princeps-Ptilophyllum assemblage whose important members are Todites denticulate, Conipteris hymenophylloides, clathropteris meniscioides, Marattiopsis? sp., Cladophlebis raciborskii, Ptilophyllum sp., Otozamites sp., Swedenborgia cf. crymerioides.
Age
Depositional setting
The formation represents a set of fluvial, lacustrine and swamp-facies deposits.
Additional Information