Abstract This paper studies the distribution of gold and the trace element geoche mistry related to gold metallization within Wuqiangxi Formation of Proterozoic Banxi Group in Mobin area, southwestern Hunan. Wuqiangxi Formation of this area is characterized geochemically by obvious depletion in Au, Hg and Sr and enrichment in As and Sb with Co/Ni>1 and Au/Ag and Sr/Ba very low. The spatial distribution of gold shows some regularity: from the distant strata to the wall rocks beside the ore vein within the ore deposit, five zones can be successively detected, i. e., background zone, depleted zone, enriched zone.deple-ted zone and enriched zone, with the last four zones forminga conjugate system. The two processes of gold depletion resulted from two separate hydrothermal leaching processes different from each other in time, scale and geochemical characteristics. Such multi-stage leaching led to two-phase metallization In the Mobin gold deposit. The appearance of the depleted areas or zones of gold and other ore-forming elements seems ubiquitous to some extent, thus serving as an important indicator in ore prospecting.
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