Ore-controlled Mechanism and Geochemical Characteristics of Gold-bearing Formation in Northwest Jiangxi Terrain

Based on the geological and geochemical studies on the Middle Proterozoic Jiuling Group in the Northwest Jiangxi Terrain, it is ascertained that this group is a kind of Au-bearing formation with Au-Ag-As association, and the volcanism is the key to its foundation. The Jiuling Group can be divided into two geochemical groups: high-Au layers and low-Au layers, which is due to the inhomogeneous metamorphic reformation. The discriminant functions F_1& F_2 can be established by means of Au, Ag, As, Ti, Cr, V, etc. eleven elements, and the diagram of F_1-F_2 is the distinguishing sign of the Au-bearing formation. Based on the systematic studies on two types of gold mineralization, namely, solo gold with metamorphic fluid and Au, Ag, etc. polymetallic association with magmatic fluid, the authors establish the metallogenic model of gold deposits in the area.     

赣西北地体含金建造地球化学特征及其控矿机制

通过对赣西北地体中元古界九岭群进行的地质地球化学研究,确定该群为一Au-Ag-As-(Sb)组合的含金建造,火山作用在含金建造形成过程中起着关键作用。九岭群含金建造划分为高Au和低Au两类地球化学群,不均匀变质改造作用是二类地球化学群形成的主导因素,可利用Au, Ag, As, Ti, Cr, V等11种元素建立判别函数F_1和F_2,构造作为含金建造判别标志的F_1—F_2图解,系统探讨了区内变质热液型单金矿化和岩浆热液叠加型Au, Ag为主多金属矿化等二类金矿化类型,建立了本区金矿床的成矿模式。     

基于可见近红外高光谱的东北盐渍土盐分定量模型研究

为实现东北苏打盐渍土盐分的定量反演,利用光谱测量技术,建立了土壤反射光谱与土壤盐分含量之间的偏最小二乘回归模型;探讨了利用反射光谱预测土壤盐分含量的可行性;分析了不同光谱处理方法、不同重采样间隔条件下建模的精度。结果表明：基于反射光谱进行土壤盐分的定量预测是可行的。平滑后的光谱预测精度比平滑前的预测精度明显提高。平滑后倒数对数变换能够有效去除噪声影响,所建立的模型预测精度最高(R2=0.6677, RPD=1.61)。能够满足盐分预测精度的最大的重采样间隔为8 nm。为大规模卫星遥感监测盐渍化土壤时空演变提供了科学的参考依据。