Nanshuangyashan Fm
Type Locality and Naming
The named section is located about 3 km east of Nanshuangyashan in Baoqing County, Heilongjiang Province. In 1962, the Seventh Geological Team of Heilongjiang Geological Bureau named the Upper Triassic, which is mainly composed of tuff and clastic rocks, as the Nanshuangyashan Formation by taking Nanshuangyashan section in Baoqing County as the named section.
Synonym: In 1959, Wang Xiuzhang named the Marine Upper Triassic in the Nadan Hadaling area of eastern Heilongjiang Province as "Qingjiang Rock Group", but he did not specify a named section.
Lithology and Thickness
It is composed of tuff, tuffaceous sandstone, siltstone and tuffaceous mudstone with a thickness of 1897 to 2516 m
Relationships and Distribution
Lower contact
It is in fault contact or unconformable contact with the underlying Warrissian granite
Upper contact
Regional extent
GeoJSON
Fossils
Entomonotis cf. tenuicostata, E. ochotica baoqingensis, Plagiostoma nuitoense, Natiria sp.
And so on; Entomonotis jakutica, E. scutiformis, E. ochotica and crinoid stem produced in the middle; The upper bivalves Parainoceramus sp., Pleuromya cf. submusculoides, Opiria sp., Oxytoma sp. and so on; Plant fossils Neocalamites sp., Todites wiliamsoni, Sphenopteris sp., Stenopteris sp., Yabiella sp., Sphenobaiera? sp., Nilssonia sp., Anomozamites sp., Podozamites lanceolatus, Elatocladus sp. and so on. Also produces brachiopod Spiriferina sp., ostracod Hungarela, etc.
Age
Depositional setting
Marine volcanic eruption - sedimentary rock sequence.
Additional Information