Tai'antun Fm
Type Locality and Naming
It was named by Zhong Weicheng, Yang Yu in 1964. The naming section is located in the vicinity of the Tai’antun Village, Shangzhi County, Heilongjiang Province, with its reference section being situated at North Hills west of Yangmugang area of Shangzhi County.
Synonym: （太安屯组）
Lithology and Thickness
Lower member is composed of yellow-brown and dark-grey conglomerates and sandy conglomerates, intercalated with thin-bedded tuffaceous sandstone, argillaceous slate and acid lava. Upper member is characterized by the increase in volcanic materials and being composed mainly of grey-white rhyolitic tuff-lava and acid lava-conglomerate, intercalated with tuffaceous siltstone and argillaceous slate. The total thickness of the strata is about 1000 m.
Relationships and Distribution
Lower contact
The formation is in an unconformable contact with the underlying Paleozoic Erathem or the Variscan granite.
Upper contact
No top has been found. Regionally, it is in an unconformable contact with the overlying Maoershan Fm volcanics.
Regional extent
It is distributed un-extensively and is largely concentrated in the areas of the Yangmugang and Dazhujuan Mts of Shangzhi County.
GeoJSON
Fossils
In the area of the Bianmian Mts of Binxian County and the Dongshan Mts of the Yaosidao River area the formation yields a small amount of plant fossils such as Neocalamites sp., Cladophlebis sp., Pterophyllum sp., Taeniopteris sp., Ginkgo sibirica, Sphenobaiera huangi, S. longifolia, Pityophyllum longifolium and Podozamites sp. In the Shenshu area of Tieli County it yields insect fossils as represented by Samarura sp., Mesoneta sp. and Mesoleutra sp., as well as plant fossils such as Czekanowskia sp. and Podozamites sp.
Age
Depositional setting
The formation belongs to eruptive-facies and fluvial-lacustrine deposits formed during the eruption interval.
Additional Information