Hetaoping Fm

No type section was assigned when the formation was erected. An auxiliary section, the Hetaoping-Maozhupeng section in Wayao Township, Longyang, Baoshan, Yunnan Province was proposed by Zhang (1996) as representative section of the formation. The section lies about 12 km west of the seat of Wayao Township (99°08’E, 25°26’N), and is measured by the No 1 Brigade of Yunnan Regional Geological Survey Team in 1979. The Hetaoping Formation was firstly published by Yunnan Bureau of Geology (1974). The name is derived from Hetaoping Village in Wayao Township, Longyang District, Baoshan City, western Yunnan Province. The name was originally appeared in a 1967 manuscript by Luo Huilin from Yunnan Institute of Geology.

Synonym: （核桃坪组）

In general, the Hetaoping Formation is a classic sequence. It is roughly divided into three lithological parts. Lower part, 305 m thick, consists of yellowish green and greyish green metamorphic sandy shale and siltstone with more silty content in its lower part; Middle part, 436 m thick, consists of mainly light greyish green metamorphic shale and silty shale, intercalated occasionally with same colored siltstone and dark grey marlstone; Upper part, 126 m thick, consists of light yellowish green and greyish green, thin-bedded metamorphic siltstone and silty shale, intercalated with minor grey, thin-bedded limestone and marlstone. As the formation’s base is unknown in the auxiliary section, the formation has an incomplete thickness of 867 m.

In the auxiliary section, the lower part of the Hetaoping Formation yields trilobite Cyclolorenzella sp.; the middle part yields trilobites Bergeronites sp., Cyclolorenzella sp., Liaoningaspis sp. and Wayaonia hetaopingensis; and the upper part yields Bergeronites sp. In other locality, the formation yields additional trilobites Aulacodigma? sp., Blackwelderia baoshanensis, B. sp., Chatianta hetaopingensis, Homagnostus sp., Liaoningaspis yunnanensis, Parashengia elongata and Shengia tumida.