Banshidingzi Fm
Type Locality and Naming
It was named by Li Wenmin in 1973. The naming section is located in the area stretching from Banshidingzi to the Taiyang Ridge, Shuangyang County, Jilin Province.
Synonym:（板石顶子组）
Lithology and Thickness
It represents a set of slightly metamorphosed conglomerate, sandstone and siltstone, intercalated with a small amount of acidic volcanoclastic deposits, yielding abundant plant fossils, with a thickness of about 540 m.
Relationships and Distribution
Lower contact
It overlies unconformably the underlying Fanjiatun Fm of the Late Permian. Regionally, the next older unit is the Dajianggang Fm of late Triassic (column TJ10b) or the Lujiatun Fm of early Triassic (column TJ10a).
Upper contact
Regionally, the next younger unit is indicated as Taiyangling Fm
Regional extent
It is distributed largely in the Dajianggang area to the east of Banshidingzi in the southern part of the Shuangyang Basin till the northern part of Liushuhezi area. Its thickness varies from 312 m to 645 m. The strata there are slightly metamorphosed.
GeoJSON
Fossils
It contains an early assemblage of the Coniopteris-Phoenicopsis flora, important members of which are: Equisetum asiatica, E. laterale, E. sarrani, Neocalamites sp., Cladophlebis asiatica, C. cf. bitchuensis, C. gigantea, C. raciborskii, Coniopteris hymenophylloides, Ctenis sp., Phoenicopsis angustifolia and Pityophyllum longifolium.
Age
Depositional setting
The formation belongs to intermontane-basin alluvial-fan and fluvial deposits, intercalated with acid volcano-eruptive deposits.
Additional Information