GEOCHEMICAL CHARACTERISTICS AND GENESIS OF STRATABOUND GOLD DEPOSITS IN JIANGNAN GOLD METALLOGENIC BELT

This paper, based on the geochemical study and comparison of the gold-bearing formations and stratabound gold deposits hosted by the formations in the belt, shows that the most outstanding geochemical characteristics of the strata-bound gold deposits in the Proterozoic Jiangnan Metallogenic Belt, namely "Jiangnan-type" gold deposits, are conjugated occurrence of gold-depleted strata associated with high frequency gold mineralization in regional scale and negative gold anomaly in the wall rock of gold orebodies in the local range, concentration of the low-abundance elements such as Au, Sb, W and As, and impoverishment of base metals in the ore. Their ore-forming solutions have a temperature range of 160—390℃, intermediate salinity mostly from 4 to 10 wt% NaC1 equiv., nearly neutral to weak alkaline, and are reduced, rich in HCO, ΣS and poor in C1. It is suggested that the ore-forming elements of the deposits mostly come from the gold-bearing formations and the metallogenic processes are majorly re