Metallogenic characteristics and genesis of typical gold deposits in Victoria Lake gold field in Tanzania

The Victoria Lake gold field has experienced complex structural deformation, magmatic activity and mineralization evolution, forming rich gold resources.Based on the study of geological features of typical gold deposits, source of ore-forming fluid and ore-forming age of the Victoria Lake gold field in Tanzania, this paper explores the genesis of the deposit and the gold precipitation mechanism.The gold deposits are mainly hosted in the stratigraphic units of the greenstone belt, and the ore bearing structures are mainly ductile-brittle shear zones with roughly the same strike as the greenstone belt.The homogenization temperature range of H₂O-CO₂ fluid inclusions in gold ores is mainly 300~400℃, and the salinity range is 14%~22%.The ore-forming fluid belongs to medium-high temperature and high salinity fluid; The source of ore-forming fluid is mainly magmatic water, and part of metamorphic hydrothermal fluid also participates in the ore-forming process.The mineralization age of the Lake Victoria gold deposit in Tanzania is 2700~2620 Ma, which is Archean; The deposit type is a medium-high temperature hydrothermal gold deposit controlled by shear belt.The above research progress is of certain theoretical guiding significance for the prospecting and exploration of gold deposits in the greenstone belt of Africa.