Abstract:The South China Sea and its adjacent areas have diverse topography and abundant provenance materials, which provide a material source and accumulation environment for the formation and distribution of marine solid mineral resources. In order to systematically find out the distribution of placer resources in the entire South China Sea and its adjacent areas, this paper analyzes the distribution characteristics and prospects of useful mineral placer resources and building sand resources, and summarizes the placer mineralization model through particle size and clastic mineral identification of surface sediment samples from 2606 stations in the South China Sea and adjacent areas. The results show that the promising minerals in the South China Sea and the adjacent areas mainly include zircon, ilmenite, rutile, anatase, monazite and garnet. High grade ore occurrences of heavy minerals are mainly concentrated in the northeastern and southern continental shelf of the South China Sea, and the Philippine basin. The anomalous areas of heavy minerals are mainly located in the shallow waters of the peripheral continental shelf of the South China Sea, the shallow waters of the outer shelf of Vietnam and the Philippine Sea basin. Among them, the anomalous range of zircon grades is the largest, and the area with industrial grades is also the largest; followed by magnetite, ilmenite, monazite; anatase and rutile are equivalent; garnet grades are the smallest. According to the distribution law of placer deposits, tectonic background, metallogenic conditions and characteristics of metallogenic elements delineate 24 useful heavy mineral placer metallogenic prospect areas and 6 metallogenic belts. There are 9 prospective areas of construction sand with a sand content of more than 50% in the sediments (0. 063~2 mm), mainly distributed in the waters north of the line from the southwest of Hainan Island to the southern part of the Taiwan Strait, followed by Reed Beach and Wanan in the southern part of the South China Sea. The sea area near Zengmu Shoal and Zengmu Shoal is extremely rare. Based on the distribution characteristics of placer resources in the South China Sea, five types of marine sand metallogenic models including nearshore type, tidal sand ridge type, buried paleochannel type, gorge type, and shelf slope break zone type have been initially established to provide guidance for understanding sand mineral resources in the South China Sea. They also provide reference significance, directions and suggestions for further exploration of sand mineral resources.