Element-assemblage Zoning Features of Gold Deposits in the Cambrian Silicalite Formation, Western Qinling

The gold deposits, occurring in the south subzone of western Qinling, are the only typical and important strata-bound gold deposits, which are associated with submarine exhalative sedimentation. The gold deposits include the La’erma ore deposit, the Qiongmo ore deposit and the Yaxiang ore occurrence. They are hosted in the Cambrian silicalite formation composed of black chert and slate. The presence of typical chert offers important evidence to evaluate the possible submarine exhalative system and its role in the formation of the gold deposits, which are closely associated with percolation and diffusion in the horizontal, vertical and axial directions. Element-assemblage zonation is clearly seen due to differences in element concentrations in different directions. Such a zonation makes gold, selenium, uranium, copper, stibium, molybdenum, mercury, etc. precipitate in the form of simple or composite orebodies. The establishment of the element-assemblage zonation is highly helpful for evaluating directly the metallogenesis of gold deposits.