Study On The Distal Mineralization Tracer In Shizhuyuan Ore Deposit,hunan Province

The Shizhuyuan deposits are located in the Nanling metallogenic belt,with large reserves,high grade and rich minerals.Centering on the Qianlishan granite complex,the W-Sn-Mo-Bi mineralization zone,the Pb-Zn mineralization zone and the Hg-Sb mineralization zone with a north-south span of 8 km are formed from the proximal end to the distal end.The predecessors lacked systematic analysis and research on the influence range of the Qianlishan granite complex and the relationship with diatal mineralization of the Shizhuyuan.This paper mainly uses the stable isotope tracing method to explore the relationship between the distal mineralization and the Qianlishan granite body,revealing the causes and material sources of the distal mineralization.?1?From the proximal end to the distal end,the?¹⁸O values of the whole rock carbon-oxygen isotope samples range from 6.5‰to 25.5‰,and the?¹³C values range from-4.3‰to 2.5‰.The farther away from the thermal anomaly center of the Qianlishan granite complex,weaker the water rock reaction,greater the data values,the more biased toward the carbonate rock.At the distal,due to the low W/R ratio,the?13C value varies little?2‰?and the?18O value changes greatly?10‰?.The?¹⁸O and?¹³C values of most samples are higher than the magmatic but at the same time lower than the?¹⁸O and?¹³C values of the unaltered marine limestones.?2?From the proximal end to the distal end,the majority of the?¹⁸O values of the calcite samples range from 6.8‰to 13.1‰,the majority of the?¹³C values range from-2.6‰to 1.2‰.The?¹⁸O and?¹³C values of most samples are higher than the magmatic,but at the same time lower than the?¹⁸O and?¹³C values of the unaltered marine limestones.The limestone and calcite samples collected at the five sampling points found that the calcite samples were more inclined to the Qianlishan granite value than the limestone?¹⁸O and?¹³C values.?3?From the proximal end to the distal end,ranges of the?¹⁸O values of the quartz samples from 2.2‰to12.3‰,and the variation trend of the?¹⁸O is farther away from the thermal center of the Qianlishan granite complex,showing the lower of the data values.A small part of the?¹⁸O value shifts to the atmospheric precipitation value range,so atmospheric precipitation participates and influences.?4?From the proximal end to the distal end,the?³⁴S values of mineral samples ranges from-2.3‰to 6.5‰,the average is 2.93‰.It has the characteristics of deep source sulfur.The maximum and minimum differences are 8.8‰,the homogenization of sulfur from high-temperature magma sources is complete and belongs to a single magma source.Therefore,in the Qianlishan postmagmatic stage,atmospheric precipitation continuously added and water/rock reactions became weaker and weaker during the magmatic hydrothermal fluid migrating to the south,resulting in the decrease in temperature and the decrease in sulfur fugacity.The folds and fissure structures in the Qianlishan area are very developed,and sulfides are continuously precipitated into ore.Therefore,a series of deposits within 8 km south of the Qianlishan granite complex should be affected by the Qianlishan magma thermal system and enriched mineralization.