The Geological Characteristics And Genesis Of The Lingjinyikuang Gold Deposit,Henan Province,China

Lingjiyikuang gold deposit is one of the representative auriferous quartz vein type gold deposits in the Xiaoqingling gold district.A detailed geological and geochemical study has been carried out on the Lingjiyikuang gold deposit,with a focus on an analysis of the link between wall-rock alteration and gold mineralization,genesis of the deposit,and summing up the mineralization rules,carrying out mineralization prediction in the Xiaoqingling district.The hydrothermal alterations are generally developed on both sides of the orebodies and are zoned.From the orebody to the fresh wallrock,the following zones of alteration can be distinguished: a beresitization alteration zone,a silicification alteration zone,an alkaline metasomatism alteration zone,and a chlorite-epidote alteration zone.Beresitization alteration zone and alkaline alteration zone are most closely related to the gold mineralization in the Lingjinyikuang deposit.Isocon diagram of mass-balance calculation analysis shows that(1)Au,Cu,Pb,and Zn in the metamorphic rocks were reactived and moved into the ore-forming fluid during the forming process of the alkaline metasomatic rocks;(2)the element exchange between the fluid and the surrounding rock is weak during the forming process of the silicified rocks;(3)the gold deposition occurred and was caused by the sulfidation of Fe-rich wall rocks during the forming process of the beresitization rocks;(4)the chlorite-epidote alteration is low temperature alteration,marking the end of gold mineralization.The trace and rare earth elements distribution patterns of the ores in the Lingjinyikuang gold deposit are consistent with those of the alkaline metasomatic rocks and beresitization rocks,indicating that they are the products of the same mineralization system.Lead isotope data show that the ore-forming materials of the Lingjinyikuang deposit were from the Taihua metamorphic rocks.The comprehensive analysis shows that the structure has an important control effect on the ore distribution of body,and alterations of alkaline metasomatism and beresitization are the important controlling factors for the activation and deposition of gold,and are also the important prospecting criteria for gold deposit in the Xiaoqingling district,based on ore-controlling faults and alteration characteristics,it is predicted that there may be a very good potential for prospecting in the south of exploration line 59.