YangshanShaanxi Fm
Type Locality and Naming
The type section is located at Yangshan (actually Beiyangshan), about 80 km southeast of Zhen’an, Shaanxi. It was named by Shaanxi Party of Regional Geological Survey in 1966.
Synonym NOTE: Column 27 (Henan collision belt) had another Yangshan Fm between Miaochong and Dayangshan (better age control) => named this one "YangshanShaanxi" (maybe Chinese characters are different for these?) See notes on that one also
Lithology and Thickness
Limestone. In the Sanlichong section, Lower part is composed of light-gray, gray-white or gray-red thick-bedded or massive limestones. Upper part is of gray-black thick-bedded and massive limestones, 160−270 m thick.
Relationships and Distribution
Lower contact
Conformable contact with the underlying Xiaoyao Fm.
Upper contact
Conformable contact with the overlying Yazi Fm. [But implied by Permian column 70 to also underlie the Sanlichong Fm)
Regional extent
Distributed around Beiyangshan in the east segment of south Qinling Mts., being best developed in the Xikou area of Zhen’an.
GeoJSON
Fossils
The Fusulinids comprise 4 zones, which are ascending the Triticites, Pseudofusulina fecunda, Pseudoschwagerina and Robustoschwagerina-Sphaeroschwagerina zones. Conodonts consist of the Streptognathodus elegantulus-Idiognathodus hebeiensis assemblage zone in the lower part and the Streptognathodus elongatus-S. wabauensensis-S. fuchengensis assemblage zone in the upper part. And there are also the Coral (at top only) Protoivanovia orientalis assemblage zone and the Brachiopod Enteletes lamarcki-Neopugilis incrassatus assemblage zone.
Age
Depositional setting
It is interpreted as platform neritic deposits
Additional Information