Hewanjie Fm
Type Locality and Naming
The type section is located at the Yangliu Township, Baoshan County, Yunnan Province. It was named by the Yunnan Geological Survey in 1980.
Synonym: Hewanjie Gr
Lithology and Thickness
It is characterized by a set of stable dolomites, which is commonly known as “broken limestone”. It is mainly consisting of light gray thick layer to massive fine crystalline dolomite, intercalated with breccia fine crystalline dolomite and intra-aggregate clastic micrite dolomite. The thickness is about 500 m.
Relationships and Distribution
Lower contact
The Hewanjie Fm is false conformable in contact to the underlying Daaozi Fm (P3)
Upper contact
It is false conformable in contact to the overlying Niuhetang Fm with dolomites. . [Tong et al. (2019, Triassic integrated stratigraphy and timescale in China, Science China: Earth Sciences, v. 62, no. 1) interpret that Ladinian is absent at this boundary => disconformity.] Around Baoshan, Shidian County, it is overlying the Woniushi Fm (C3) and Dingjiazhai Fm (C3).
Regional extent
The formation is distributed in Baoshan County, Yunnan Province. The lower part near Baoshan County is dolomite, and the upper part is limestone. The thickness varies greatly. The shore of the Handing River is only more than 300 meters thick, while Baoshan County is more than 900 meters thick, showing a trend of thinning in the south and thick in the north.
GeoJSON
Fossils
Bivalves: Neoschizodus lavigatus, N. cf. matus, Posidonia cf. bosniaca, Castatoria cf. proharpa, C. cf. goldfust, Plagtostoma cf. beyrichi; Foraminifera: Glomospira sp., Multidiscus sp. and Gastropods.
Age
Depositional setting
It is interpreted as supra-tidal zone or lagoon facies.
Additional Information