Lutiaoshan Fm
Type Locality and Naming
The type section is lies on the north hill of Tianshuijing, about 150 km east of Mingshui, Subei, Gansu. It was named by the No. 2 Gansu Party of Regional Geological Survey in 1970, and published in 1974.
Synomyn: Lütiaoshan Fm (with umlaut)
Lithology and Thickness
Conglomerate and Claystone. A suite of marine clastic rocks, occasionally intercalated with volcanic deposits. In the type section, the Lower sandstone-conglomerate member is dominated by yellow-green conglomerate, pebbly grit and greywacke, intercalated with calcareous sandstone and marble, 984 m thick. The Upper slate member consists mainly of gray-black and gray-green phyllite to slate, intercalated with yellow-green siliceous slate, top unseen, and thickness >940 m.
Relationships and Distribution
Lower contact
Unconformable contact with the underlying Que’ershan Fm (Queershan Fm; mid-Devonian)
Upper contact
Regionally, the next younger units are the coeval Baishan Fm volcanics and the Hongliuyuan Fm clayey limestone
Regional extent
Distributed in Lütiao Mountain, Shalingaolai, etc., close to the Sino-Mongolia border in the Beishan area.
GeoJSON
Fossils
Marble in the basal part contains Brachiopods Syringothyris sp. and Ptychomaletoechia sp., Coral Caninia sp., etc. In the Lower part of the Lutiaoshan Fm at about 10 km north of the type section, brachiopods Syringothyris cf. texta and S. altaxa are found, correlatable to the Meilukahe Fm of early-middle Visean at Boluohuoluo Mt., North Tianshan Mts.
Age
Depositional setting
It is interpreted as marine clastic rocks
Additional Information