Determination of age and source constraints for the Bake quartz vein-type gold deposit in SE Guizhou using arsenopyrite Re-Os chronology and REE characteristics

Abstract

The Bake quartz vein-type gold deposit is one of the most well-known gold deposits in SE Guizhou. The mineralization age of auriferous arsenopyrite determined using Re-Os chronology is 412 ± 21 Ma (MSWD = 2.6), which is in good agreement with the regional-scale geologic evidence and confirms that the Caledonian was an important gold metallogenetic period in the Xuefeng region. Contrastingly, the high initial ¹⁸⁷Os/¹⁸⁸Os ratio (2.7 ± 1.2) suggests a crustal source for the ore-forming material of the deposit. Furthermore, the REE patterns, Eu/Eu*, Ce/Ce* and Y/Ho ratios of the arsenopyrites are all similar to those of the wall rocks, indicating that the ore was perhaps derived from the wall rocks belonging to the Xiajiang Group.