Geological Features and Prospecting Direction of the Xintaizi Gold Ore Field in the Northern Margin of the Xikang-Yunnan Axis

The Xintaizi gold ore field belongs to a gold metallogenic belt of the Hercynian shear zone,which is affected by the Danba arc structure,ductile shear structure of the Daduhe River and Hercynian basic-ultrabasic magma activity.This gold metallogenic belt is characterized by abundant mineral resources,and is a precious metallic metallogenic belt in the western margin of the Yangzi block.This paper analyzes the geological conditions for mineral deposits,ore-controlling structure,ores and minerals and alteration association and suggests that the ore deposits are of the hydrothermal vein type with low temperature and shallow layers and of the altered rock type in fractured alteration zones,which are controlled by strata,structures and magmatic rocks.This deposit shows a good potential of forming small and medium-sized gold deposits.(1) The ore-forming materials of this precious metallic metallogenic belt in the Xintaizi gold field and its neighboring gold field are of the Sinian Kangding Group.(2) Deep faults serve as the main migration conduits for multi-source ore-forming materials,and crustal source magma provides heat for the activation of ore-forming materials.(3) The Carbonaceous finegrained clastic rock of the Devonian Weiguan Group and black rock series like the phyllite are organic chemical barriers,making it possible to precipitate gold element inside the metallogenetic fluid from bottom to top and to realize mineralization.