摘要
通过对西秦岭岷礼成矿带化探数据中Au、Cu、Pb、Zn、W和Sn进行分形模型研究,发现Au和Sn具有多层次的地球化学场,指示该区Au和Sn具有更高的富集程度和成矿潜力。通过因子分析法得到的第一主因子(F1)的元素组合为Co-Cr-Cu-Ni-Ti-V-Zn,代表了晚古生代地层,其得分分布与区域铜、金矿化套合较好,表明矿化可能来自于该套地层。代表铅—锌、钨—锡矿化的因子(F2~F4)得分与晚三叠纪侵入岩体一致,表明该系列矿化与岩浆作用相关。F5因子只含有Au元素,表明金矿化更可能受区域复杂褶皱断裂系统的控制。研究结果将为岷礼成矿带地质找矿提供新的方向。
Minxian-Lixian metallogenic belt is rich in polymetallic resources in the west Qinling area,which has a complex tectonic history.However,there is still a lack of research on the geochemical anomaly patterns and ore-controlling factors of different types of deposits,which restricting the deployment of ore prospecting and exploration.To solve the problems,data of stream sediment geochemistry is utilized to study metallogenesis at a regional scale,to reveal the characteristics of distribution and association of geochemical elements,and thus provide important guidance for prospecting and exploration.A total of 4095 samples were collected in the area and centered log-ratio(CLR)transformation was performed in the following to alleviate the skewness of raw data and make the element concentration tend to a normal distribution.Based on the fractal theory,Concentration-Area(C-A)models of Au,Cu,Pb,Zn,W and Sn have been established.It is found that elements of Au and Sn have multiple levels of geochemical fields,indicating that they have higher degree of enrichment and metallogenic potential.The geochemical anomalies of Au,Cu,Pb and Zn in the north subbelt can be roughly divided into two categories.One is related to the Late Triassic intrusive magmatism,where Suolong and Mawu gold deposit and Daijiazhuang Pb-Zn deposit expose.Another is related to the regional complex fault-fold system(Minxian-Tanchang fault and the Diebu anticline),where Zhaishang super-large gold deposit and several mineralization points expose.Also,anomalies of W and Sn show a strong spatial correlation with the Wuduojinhua pluton,hosting many mineralization points.Before performing factor analysis,Bartlett test of sphericity and KMO test were used to test the relevance of the selected data.The results show that the KMO value is 0.91,and Bartlett’s sphericity test also meets the conditions of factor analysis.The results of factor analysis indicate:(1)The element association of the first factor(F1)is Co-Cr-Cu-Ni-Ti-V-Zn,which represents the Late Paleozoi
作者
马承
宋伊圩
孙彪
王占彬
MA Cheng;SONG Yiwei;SUN Biao;WANG Zhanbin(Xi’an Center of Mineral Resources Survey,China Geological Survey,Xi’an 710100,Shaanxi,China)
出处
《黄金科学技术》
CSCD
2021年第4期489-499,共11页
Gold Science and Technology
基金
中国地质调查局项目“甘肃寨上金矿岩金普查”(编号:DD20191018)资助。
关键词
分形模型
因子分析
地球化学特征
矿化类型
成矿潜力
岷礼成矿带
fractal model
factor analysis
geochemical characteristics
mineralization types
metallogenetic potentiality
Minxian-Lixian metallogenic belt
