摘要
Fifteen geochemical provinces of gold were delineated based on the geochemical data of 1:200000 Regional Geochemistry-National Reconnaissance(RGNR) project covering about 6000000 km2,and 1:1000000 geochemical mapping projects in eastern Tianshan,Sino-Mongolian border and eastern Heilongjiang totaling about 860000 km2,in China.It was found that all gold geochemical provinces related to gold metallogenic provinces or ore districts have nested hierarchical geochemical patterns.The patterns are induced by rocks with high background values of gold,mineralization processing and secondary dispersion by ore deposit weathering.Rocks have provided initial endorment accumulation for the gold provinces,mineralization processing led to the further enrichment of gold,and the secondary dispersion of ore body weathering form concentration centers of the anomalies.Micro-and nano-particles of gold widely observed in geochemical samples play important role in the formation of large-scale geochemical anomalies,because micro-and nano-particles of gold are mobile to be transported by various forces.