Abstract The alterations related to gold minerlization in the Luerba gold deposit are silicification, pyritization and carbonatization, which find expression in the existence of limonite, jarosite and kaolin at surface. Litho-geochemistry of the ore deposit indicates that Au and As are closely related to each other, Sb, Hg, Au and As constitute near-ore or distal indicators of Au, and Au, As and Zn stably exist in such minerals as pyrite or arsenopyrite. These relationships are inherited in soil but disintegrated in stream sediments. Therefore, Au and As can be selected as indicator elements in litho-geochemical survey and soil geochemical survey, whereas Au, As, and Sb should be taken into account together in stream sediment survey. The dilution or concentration of Au in surface materials only markedly manifest itself in the mining area, and basically takes place at the step of migration from soil to stream sediments. The mechanical mixing and sorting of the stream and the sieving during sample preparation are decisive factors responsible for the reasonable decrease of gold content. In the secondary material of the background area, there is no remarkable dilution or concentration of gold.
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