基于红外光谱技术的赣南铜岭下铜多金属矿床蚀变及矿化特征研究

江西赣南地区是中国重要的多金属矿集区，成矿潜力大，随着矿产勘查进入深部找矿的新阶段，传统勘查手段难以支撑，亟需新的方法和思路进一步来指导找矿工作。文章以江西赣南地区铜岭下铜多金属矿床为例，采用短波红外+热红外光谱技术，结合矿物学和矿物地球化学手段，厘定了矿区蚀变矿物组合及空间展布特征，分析了光谱特征与矿化品位之间的关系，探讨了铜岭下矿床中典型蚀变矿物的形成与演化过程，构建出铜岭下矿床的光谱勘查模型。研究发现，矿区北部Cu-Mo矿化分布于花岗岩体顶部，以绢云母族矿物为找矿标志；矿区中部Cu-Zn矿化处于花岗岩体侵入的地层接触带，以绿泥石低Pos2250值（< 2243 nm）以及蛇纹石和断裂特征分布为找矿标志；矿区南部W-Sn-Cu矿化与石英细脉相关，总体与蚀变矿物关系不大，主要以岩石裂隙为找矿标志。北部钻孔ZK9-3和ZK9-4伊利石波谱IC值反映出岩体侵入深度大，推测其位置距离热源中心更近；绢云母2200 nm波长变化结果显示：成矿流体可能来源于矿区北部；矿区中部绿泥石以富镁（铁）绿泥石为主，Pos2250值从致矿岩体到接触带附近呈由高变低的趋势。研究区成矿环境复杂，由北向南形成了蚀变花岗岩型（Cu-Mo）-构造控制下的弱矽卡岩型（Cu-Zn）-石英脉型（W-Sn-Cu）的复合成矿体系。

Alteration and mineralization characteristics of Tonglingxia copper polymetallic deposit in Gannan based on infrared spectroscopy technology

The Gannan region in southern Jiangxi Province is a significant ore concentration area of polymetallic mine-ral deposits in China with high mineralization potential. As deep exploration for mineral resources progresses, traditional exploration methods prove inadequate, necessitating the urgent adoption of new methods and approaches. This study focuses on the Tonglingxia copper-polymetallic deposit in the Gannan region and employs short-wave infrared spectroscopy in conjunction with thermal infrared spectroscopy. By utilizing mineralogy and mineral geochemical methods, it establishes the composition and spatial distribution characteristics of alteration minerals in the deposit area. Furthermore, it examines the relationship between spectral features and the grade of minera-lization, investigates the formation and evolution process of typical alteration minerals in the Tonglingxia deposit, and constructs a spectral exploration model. The findings unfold as follows:Cu-Mo mineralization primarily occurs at the top of the granite body in the northern part of the deposit, with sericite minerals serving as exploration indicators. In the middle part of the deposit, Cu-Zn mineralization is located in the contact zone of the granite intrusive body and can be identified through low Pos2250 values (< 2243 nm) of chlorite, as well as the presence of serpentine and fractures; In the southern part of the deposit, W-Sn-Cu mineralization is associated with quartz veins and demonstrates limited overall correlation with alteration minerals, indicating a predominant occurrence of mineralization infilling rock fractures. The IC values of illite spectra in drill holes ZK9-3 and ZK9-4 in the northern part indicate a greater depth of granite intrusive body, suggesting closer proximity to the heat source center. Additionally, the variation of sericite wavelength at 2200 nm on spectrum suggests that the mineralizing fluid may originate from the northern part of the deposit. Chlorite in the central part of the deposit consists mainly of magnesium-rich chlorite, and the Pos2250 value exhibits a decreasing trend from the granite intrusive body to the contact zone. The ore-forming environment in the study area is complex, resulting in a composite ore deposit system that transitions from an alteration granite type (Cu-Mo) in the North to a weak skarn type (Cu-Zn) controlled by structures and finally to a quartz vein type (W-Sn-Cu) in the South.