| Xuefeng arc structure belt means the arc uplift belt of the Xuefeng ancient mainland which located in the Jingxian-Yiyang section in the territory of the Hunan Province, east of Yuanling-Mayang Basin and west of Chengbu-Xinhua fault. The east-west width is about60km, and the north-south length is about240km.The overall structure present long and narrow belt of NE-NEE trending, convergence in north-east segment and divergence south-west segment.Based on the gold-antimony deposit of Xuefeng arc structure belt as the research object, from the aspects of ore-forming geological background, ore deposit geology characteristics (ore characteristics, orebody characteristics, altered characteristics, mineral typomorphic characteristics) and so on, through analyzing the typical gold-antimony deposit, gold antimony regularity of mineralization and enrichment in the area are summarized in this paper. By emphatically analysing on ore controlling structure of gold-antimony deposit, important theoretical basis is provided for gold-antimony prospecting practice in the same structural type condition in this region. On this basis, matellogenic regularity of deposit and advantageous prospecting criteria are also summed up. At the same time, metallogenic model of gold-antimony deposit is established and metallogenetic prospecting prediction is conducted.The main contents of the paper can be summarized as the follows:1. NE-trending structure belt (Xuefeng arc ductile shear zone) is considered to be the ore-transmitting structure and NW-trending fault zone is the main host structure in this area. Mineralization is most important influenced by ductile shear zone. Both NE-trending and NW-trending compose the main tectonic framework of ore district together.2. Gold-antimony mineralization zone is controlled by NE-trending fault zone, gold deposits are compound controlled by NE-trending and NW-trending faults, and gold orebody is compound controlled by NW-trending and NE-trending fault secondary faults.3. Through systematic analysis on the typical gold deposit(mobin, woxi, chanziping) and typical antimony deposit(zhazixi, banxi) of Xuefeng arc structure belt, mineralization enrichment regularity of deposit is summarized which provide important basis for prospecting direction of deposit.4. By research on geochemical data such as sulfur, lead, hydrogen, and oxygen isotope, an important conclusion is put forward that metallogenic material is mainly from banxi group and lengjiaxi group underlying basement formation of proterozoic. Metal elements in the partial host strata also participate in mineralization. Metamorphic water occupies an important place in the early stage, after transformation by magmatic water, in addition to meteoric water mixing in later stage. Namely to say, matallogenic material has multiple sources, and mineralization possess multi-stage characteristics.5. By analysis and research on quartz inclusion component in mining area, it can be obtained that ore-forming temperature changes betwween140℃and350℃, salinity changes in1-12wt%NaCl, density changes in0.7-1g/cm3, pH changes between5-8, and Eh values ranged from+0.4to-0.8. It shows that ore-forming fluid properties is belong to middle temperature-low medium temperature, moderate salinity, medium density, and weak acid-neutral-weak alkaline conditions. Mineralization depth is in1-3km, which is the typical shallow-moderate depth deposit.6. Through comprehensive research on metallogenic background, mineralization characteristic, ore-controlling structure, mineralization method, metallogenic mechanism and mineralization enrichment regularity of gold-antimony deposit of Xuefeng structure belt, the segment of woxi-fuzhuxi and zhazixi-jiangkou in Xuefeng structure belt is considered to have good prospecting potential. |
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