CHARACTERISTICS OF GEOCHEMICAL ZONING IN LARGE AND RICH GOLD DEPOSITS IN SHANDONG PROVICE

East Shandong,where the most number of large and super-large gold deposits are concentrated,is the most important area for gold deposits in China. The deposits are strictly controlled by structural systems. They are characterized by multi-period and multi-stage superimposed halos,commonly with one or two major mineralozation stages. Around the ore bodies,the elements that can form anomaly are Au,Ag,Cu,Pb,Zn,As,Sb,Bi,Mo,Hg,Co,Mn,Ni,W ets. The halos formed in single stage are with obvious vertical zonation,i.e.,the strong anomaly of Hg,As,Sb(B or F)are always distributed at the top and front of ore body,while the strong anomaly of Bi,Mo,Mn,Co and Ni are at the bottom of ore body or rear halo. Au and Ag are positively correlated Cu,Pb and Zn exist at the upper part or lower part of ore bodies. The characteristics of element association and geochemical anomaly zonation of typical deposits are significant to study the superimposition of primary halo of gold deposits,to establish superimposed halo model of deposits,and to predict blind ore bodies.