Acta Petrologica et Mineralogica

The Yangchang phosphate deposit in the northwest Zhenxiong County is located at the area of Qingba Village in Wanchang Town to Liaoyeba Village in Yanyuan Town (also called Yangchang). The deposit has the characteristics of large reserves of resources, excellent ore quality and concentrated distribution of resources, and is currently the largest concealed monomeric phosphorus-rich deposit in Asia, ranking fifth in the world. The genetic type of the deposit is the shallow marine sedimentary type phosphorite deposit in the Lower Cambrian Meishucun Formation (∈₁ms). The ore body is stratified and concealed in the Yangchang anticline. Generally, the ore body develop from east to west, and the mineralization tends to be richer. To date, the Yangchang phosphate deposit has made a major breakthrough in deep mining, revealing 3 layers of phosphorite depositions, and the inferred phosphorus ore resources of grade Ⅰ+Ⅱ+Ⅲ have been discovered in 3 survey areas (Zhujiachang, Fengjiagou and Qingba Village) has a cumulative mineral thickness of 36.77 m and an average P₂O₅ grade of 22.94%. The potential phosphorite resources estimated as 132.0×10⁸ t, which effectively improves the capacity of phosphorus resources in the country, achieves the deep prospecting breakthrough of strategic minerals in short supply in the country, and has huge potential economic value and social benefits. In this paper, the formation mechanism and enrichment of the early Cambrian Meishucun phosphorus deposit is summarized systematically through the prospecting project results, and an effective deep phosphorite prospecting technology is established, which is helpful to further improve the ore-forming theory of early Cambrian phosphorus deposit, and with important guiding significance for the exploration and development of concealed phosphorus deposits in northeast Yunnan. The discovery of the super large phosphorus deposit in Yangchang has achieved a major breakthrough in deep concealed phosphorus deposit prospecting technology, greatly expanded the amount of phosphorus resources available in Yunnan Province, and laid a solid resource foundation for strengthening the storage and production of important energy and mineral resources, punning the resource economy of Yunnan Province, and building a national important phosphorus chemical industry base of 100 billion. It also provides a strong resource guarantee for the maintenance of energy and resources security of the nation.

Meishucun Formation; Yangchang anticlinal; concealed monomeric phosphorus-rich deposit; Yangchang phosphate deposit; Zhenxiong, Yunnan; Asia