摘要
甘肃省宕昌—崖湾地区是西秦岭的重要锑成矿区。通过分析该地区水系沉积物中Ag、As、Au、Bi、Cu、Hg、Mn、Mo、Pb、Sb、Sn、Zn等12种元素地球化学特征,进行了锑找矿预测研究。结果显示:Sb元素相比水系沉积物中其他元素,其浓度克拉克值、全域浓集系数(K_(k))、叠加强度(D)、变异系数(C_(v))值均显著较大,反映出Sb元素极度富集、后生叠加作用强、分布极不均匀的地球化学特点;Sb元素的成矿指数(β)最大,反映其成矿潜力最大,三叠系中Sb元素丰度平均值为(3.45~10.29)×10^(-6),是地壳背景值的17~40倍,表明三叠系是锑的主要矿源层,以扎里山组(T_(1z))和郭家山组(T_(2gj))条件最好;元素异常在空间分布上总体受区域性断层构造控制,锑矿化与Sb元素富集中心高度吻合,与As、Au、Hg元素浓集区重合度较高,揭示Sb元素为自身找矿的直接地球化学标志,Sb-As-Au-Hg为锑找矿地球化学组合标志。根据元素异常特征和找矿地球化学标志,在宕昌—崖湾地区划分出10个锑成矿靶区,新发现6处锑矿化点。
The Tanchang Yawan area in Gansu Province constitutes an important antimony mineralization area of the western Qinling metallogenic belt.This study presents a comprehensive geochemical investigation of silver(Ag),arsenic(As),gold(Au),bismuth(Bi),copper(Cu),mercury(Hg),manganese(Mn),molybdenum(Mo),lead(Pb),antimony(Sb),tin(Sn),and zinc(Zn)in stream sediments,coupled with systematic antimony prospecting prediction.Results show distinctive geochemical characteristics of antimony compared to other metal elements.Fundamental geochemical parameters including element concentration Clark value,global concentration coefficient(K k),stacking intensity(D),and coefficient of variation(C_(v))of Sb demonstrate significantly higher than those of other metal elements,reflecting the high enrichment of Sb,strong post-genetic superimposition,and highly uneven distribution.It has the highest value of mineralization index(β)for Sb,revealing the best ore-forming prospect among metal elements.The Triassic strata is considered as the main ore source beds of Sb,evidenced by average Sb concentrations(3.45-10.29)×10^(-6) exceeding crustal background levels by 17-40 times,with the Triassic Zhalishan Formation(T_(1 z))and Guojiashan Formation(T_(2 gj))representing optimal ore source beds of Sb.The spatial distributions of various element anomalies are cotrlled by regional faults,generally.The locations of Sb mineralization is highly consistent with the its enrichment center,revealing that anomaly of Sb can directely indicate the ore-forming of itself.There is a strong correlation between the mineralization of Sb and anomalies of As,Au,and Hg,so that Sb-As-Au-Hg act as a combined prospecting geochemical indicator for antimony prospecting.According to the distributions of anomaly of antimony and indicator established in this study,10 antimony perspecting target areas were divided into Tanchang-Yawan area,and 6 antimony mineralization points were newly found.
作者
张万仁
吴保祥
韦枫
杨维刚
刘杰
Zhang Wanren;Wu Baoxiang;Wei Feng;Yang Weigang;Liu Jie(Geological Survey of Gansu Province,Lanzhou 730000,China;Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;Key Laboratory of Strategic Mineral Resources in the Upper Yellow River,Ministry of Natural Resources,Lanzhou 730000,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《吉林大学学报(地球科学版)》
北大核心
2025年第5期1462-1480,共19页
Journal of Jilin University:Earth Science Edition
基金
中国地质调查局项目(1212010781066,DD20221695,DD20190379)。
关键词
宕昌—崖湾地区
水系沉积物
锑
地球化学
找矿标志
找矿预测
Tanchang-Yawan area
stream sediment
antimony
geochemistry
perspecting indicator
ore prospecting prediction
