Xiangshan Gr

Type section of Xiangshan Group is the Xiqueliang-Mopanjing section, Tongxing County (now belonging to the Shaptou District of Zhongwei City). The section is located at the border area between Tongxing County and Shaptou District about 6 km north of Mopanjing, 26 km east of Xiangshan Temple, or 35 km southwest of the seat of Zhongning County, Zhongwei City, Ningxia Hui Autonomous Region (105°31’E, 37°13’N). It was measured by the Ningxia Regional Geological Survey Team in 1960, in the type section, the group is about 3500 m thick. The Xiangshan Group was first published by the Ningxia Integrative Geology Team (1965). The name is derived from Xiangshan Temple or Xiangshan Town in Xiangshan Township, Shapotou District, Zhongwei City, western Ningxia Hui Autonomous Region. The name was originally used by the Ningxia Regional Geological Survey Team during geological survey in 1960−1964. Previously the Xiangshan Gr was subdivided into four subgroups. Based no new data of 1:50,000 regional survey, Gu (1996) proposed a subdivision into three formations for the group, in ascending order, the Xujiajuan Fm, Longzuizi Fm, and Mopangjing Fm. He also assigns the upper part of the Longzuizi Formation as Huanghejing Member. The Xujiajuan Formation corresponds to the Subgroup 1 plus Subgroup 2, and the Langzuizi Formation and the Mopangjing correspond to the Subgroup 3 and Subgroup 4 respectively.

Synonym: （香山群）

The Xiangshan Gr is mainly an epimetamorphic clastic sequence. It mainly consists of greyish green and yellowish green epimetamorphic arkosic quartzose sandstone, intercalated with thin-bedded limestone, oolitic limestone lenses, carbonaceous slate, multi-colored slate, brownish red and grey chert, siliceous dolomite, purplish red jaspery rock, conglomerate, breccia, yellowish green and brownish red phyllite. The thickness of the formation ranges from 3,310 to over 10000 m.

The limestone interbeds in the lower part of the group yields trilobite Holocephalites punctatus, Inouyia sp., Metagroulos dolon, M. nasutus, Olenoides ningxiacus, Peronopsis ovalis, and Zhongweia transversa; the thin-bedded interbeds of limestone in the middle part yields trilobites Anomocarella sp., Inouyia lubrica, Metagroulos sp., Proasaphicus sp., and Tianjingshania sp.; conodont Furnishina asymmetrica, F. furnishi and Hertzina sp.; and brachiopods Acrothele sp., Homotreta nitens, Lingulella sp., Obolus taianensis, and Westonia sp.