Xialufeng Fm
Type Locality and Naming
It was named by Bian Meinian as the Xialufeng System in 1940. The naming section is located in the vicinity of the Shawan area in the northern suburb of the Lufeng County town, Yunnan Province, with its reference section being situated in the area extending from the Shawan area to the Erzhuan Mts of Lufeng County (the Compiling Group for the Regional Stratigraphic Chart of Yunnan Province). The Xialufeng Formation was regarded as a part of the Lufeng Gr by Bureau of Geology and Mineral Resources of Yunnan Province (1996).
Synonym: （下禄丰组）
Lithology and Thickness
It is composed mainly of dark-purple, dark brown-red and dark-red mudstones and muddy siltstones, intercalated with a small amount of grey-green mudstone and yellow-green siltstone, with its basal part being composed of dark-purple conglomerate, with a thickness of 731 m.
Relationships and Distribution
Lower contact
It is in unconformably contact with the underlying Precambrian Kuyang Gr
Upper contact
Regionally, the schematic strat column indicates the next younger unit as Shanglufeng Fm
Regional extent
The formation is distributed in the Lufeng, Wuding, Yuanmou, Anning, Yimen and Eshan counties of Yunnan Province. Its lithology and thickness are varying greatly from region to region. In the Yuanhua area of Yuxi City, as well as in the Shuitang area of Yiliang County and the Dianzhong area of Eshan County the lower part of the formation is composed largely of marls, with its upper part being composed mainly of sandstone and siltstone, with a thickness of 158-1000 m. In the area to the east of the Songhuaba region, Kunming City, the area to the west of Dongchuan and Songming, as well as the area to the east of the Madian area of Xunxun County and the Xincun Village of Songming County the rocks of the formation are getting coarser, containing more conglomerates, pebble-bearing sandstones and coarse-, and medium-grained sandstones, with a thickness of 180-673 m.
GeoJSON
Fossils
It yields abundant Saurischia fauna comprising essentially the Lufengosaurus magnus, Yunnanosaurus huangi, Oligkyphus sinensis and Yunnania brevirostre. In addition, there are found to occur also the Ostracod and bivalve fossils.
Age
Depositional setting
Additional Information