Features Of Geology-geochemistry And Prognosis Of Concealed Bodies For Maoping Zinc-Lead Deposit At Zhaotong, Yunnan

On the basis of study on metallogenic setting in the northeastern Yunnan province, the REE distribution models for the fault tectonites, which distribute around the ore-bodies were classified into the division tectonic system by means of the different trend and property mechanical conversion structural planes are discussed and some ore-conduit characteristics are summarized in this paper. At the same time, the deposit genesis has been put forward after the ore-forming sources were clarified by analysis the stable isotopic (Pb, S, D, O, C) and the compositions of fluid inclusions. According to the above research, the migration and concentration of ore-forming elements are dealed with in three dimensions for the Maoping Zinc-Lead deposit. On the basis of deducing the criteria of tecto-geochemistry for the prognoses of metallogensis, the forecasting areas have been selected by means of the analytical method and theory of tecto- geochemistry in combination with the ore-forming conditions. The computer and relative software for mutirariance analysis perform these works.The Maoping zinc-lead deposit is one of the most ore-conduit deposit in this area. The trails of faults are plentiful on the structural plane, which belongs to four structural associations, and delegates four different structural systems, reflects the fault activities of four periods. The NE trending belt is mostly important ore-conduit structure, which includes the NE-trending Maoping press-shear fault and inverted Maomaoshan fold, which are the subordinate xi-type structure in the ore field.The characteristic compositions of the stable isotopic and the fluid inclusions in Maoping mineral district show that the main sources of Pb origin the Upper Earth's Crust, partly froin orogenetic belt and/or Emeishan basalt; the S isotopic composition hints sulfur sources from the seawater; The D and O isotopic compositions show that they emerge from the compound results of the magma water, metamorphic water, hosted water and rain water; the origination of the C isotopic shows that C resource strata. The ore-forming fluidfeatures enlighten that the strata had been affected by solution, leaching, exaction.The compositions of the fluid inclusion show the fluid is a hot ore-forming bittern Na+-Cl--Ca2+ type, which have a mid-low salinity, tempter, and pressure.Trace elements, especially, the strongly mineralized-tectonites and impregnated-ores' REE distraction model reflects the ore-finding symbols of geo-chemistry, and shows the fluid transferring environment or material exchanging between wall-rock and the fluid.From above discussion, we compare the patterns of mettallogeny with MVT,SEDEX deposits and Huize znic-lead deposit, the model for the Maoping deposit is "sediment-ore fluid injection".The ore-forming elements in the deposit have three main kinds of association. The first association is one of the carbonate forming element composition; the second is one of zinc and /or lead mineralization; The third is one of pyrite between the mettallogenic periods. The first element association indicates the activities between strata and ore-forming fluids; the other association indicates the main ore-forming elements and accompanying elements in the ore-forming fluid; the last association indicate the element combination of two periods pyrite.There are mineralization factor scores in every ore body distribution and can have been draw anomaly diagram as following:910 meters,Zn-In and Pb-Cu-Ge-As-Ag-Sb-Bi; 846 metersCNo. I ore body), Zn-Cu-Ge-Ag-Cd-In and Pb-As-Sb-Tl-Bi; 846 meters(No. II, III ore bodies) ,Zn-Pb-Mn-Ag-In-Sb-Bi.According to the features of fault tecto-geochemistry of the faults and ore-finding criteria, the deposit forecasting areas have suggested as following:Mineral district forecasting areas are the NE (axial plane of inverted fold ) ,SW-trend of part NW inverted limb in 846 meter height and the middle part in C\b and upper part in D3zg2 NW inverted limb;The ore-finding target areas of deposit the NE trend of No. II and No.III ore bod...