Xiaosuihe Fm
Type Locality and Naming
It was named by Northeast Institute of Geological Sciences (the present Shengyang Institute of Geology and Mineral Resources) in 1970 and published by Pen Yujing et al in 1990. The type section is located at the eastern hill by Xiaosuihe River in Dasuihe Township, about 15 km west of Jilin City.
Synonym: (小绥河组)
Lithology and Thickness
It was dominated by gray to grayish green and grayish black sandstone, siltstone and shale intercalated with minor pebbly grit stone and small-sized limestone lenses. The whole profile can roughly be subdivided into two fining-upward sedimentation cycles of from coarse-grained to fine-grained sediments.
Relationships and Distribution
Lower contact
The formation is in fault contact with the underlying Beitongqigou Fm of the Lower Carboniferous. Regionally, the next younger unit is the Zhangjiatun Fm of early Pridoli (as diagrammed on schematic strat column).
Upper contact
Its upper boundary is intruded by serpentinized peridotite. Regionally, the next younger unit is the Erdaogou Fm of early Devonian.
Regional extent
The formation, approximately 500 m thick, is so far observed only at the type section locality.
GeoJSON
Fossils
The fossils are mainly yielded in the upper circle, namely being: two assemblages of brachiopods, the Plectodonta aff. meriae assemblage including Visbyella, Plectodonta aff. meriae, Chonetes, Strophochonetes, Lissatrypa atheroidea, Coelospirella pusilla and Stegerhynchus althi; and the Mesodouvillina alatus assemblage comprising Salopina cf. submeriter, Isorthis, Mesodourillina alatus, Strophochonetes, Atrypa dzwinogrondensis, Coelospirella pusilla and Howellella nucula. There are also trilobites Encrinurus sinica, Otarion diffractum; anthozoa Parathamnopora, Fletcheria, Aulopora, Microplasma gotlandicum, Pseudomicroplasma, and bryozoa Stomatopora, Phaenopora, Semicoscinium, etc.
Age
Depositional setting
Additional Information