Abstract: The text takes the calculation of elemental vertical zoning of ZK001 in Yantonglazi Cu-Au deposit as an example, puts forward two improved aspects of calculating the Gregorian’s zoning index: in preparing the original data, normalization method of cluster analysis is used to get data format of \[0,1\] for deceasing calculation and for avoiding some manmade error; in calculating the variation degree, the reciprocal of the variation degree from traditional Gregorian’s zoning index method is used to represent the variation degree. This improvement can solve the problem that sometimes calculation cannot be carried out when some zoning index are zero. The calculation result by the method present here seems to match the geology in study area better than that by traditional Gregorian’s zoning index calculation method.

Key words: Gregorian’s method, zoning sequence, zoning index, variation degree