摘要
以新疆东戈壁钼矿为例,研究矿体上方弱胶结层不同粒级土壤中元素分布规律及成因,主成矿元素活动态赋存形式,为金属活动态测量法在戈壁荒漠区寻找钼矿提供依据。本次研究发现,Mo、Cu等成矿及伴生元素在弱胶结层(10~40 cm)中倾向于向两"极"富集,即最粗粒级(-4^+20目)和最细粒级(-160目)含量较高。在粗粒级中富集与粗粒岩屑保留了原岩矿化信息有关;在细粒级中富集与细粒土壤中粘土矿物、铁锰氧化物能有效捕获从深部矿体迁移上的活动态金属元素,形成元素含量二次叠加有关。活动态Mo、W元素主要赋存于水提取态中,活动态Cu主要赋存于铁锰氧化物态中。在大面积基岩出露的剥蚀戈壁区,采集弱胶结层粗粒岩屑样品即能反映异常;在覆盖区进行钼矿地球化学调查时,采集弱胶结层中细粒级样品为佳,能有效捕捉深部含矿信息。
This paper takes the East Gobi Molybdenum Ore in Xinjiang as an example, to study the element distributing and reason for the formation, mobile existence forms of main metallogeinc elements. Provide the basis for study conduct- ed on the MOMEO indicating effect of the molybdenum deposit in the Gobi Desert Terrain. Studies show that Mo,Cu, ect elements are enriched in coarse（-4-＋20 mesh） and fine （-160 mesh）fractions of the samples from weak cementation layer（10-40cm） over the East Gobi Molybdenum Ore. There are weathering products from partial original rock in coarse fractions containing much mineralization information; therefore, the content of elements in coarse fractions is relatively high. The relative enrichment of elements in fine fractions soil is caused by the secondary overlying content in mobile forms in fme fractions containing active metal elements migrated from the deep ore body which are captured by geo- chemical barriers that are formed by clay minerals, ferro-manganese oxides and etc. due to their strong absorbability. The mobile Mo and W are mainly extracted from water, while the mobile Cu is mainly extracted from the ferro-manganese oxideses.Sampling of coarse fraction of samples from weak cementation layer, can effectively react abnormal in the de- nuded Gobi area. Sampling of fine fraction of samples from weak cementation layer are cost-effective method for molyb- denum deposit exploration in the Gobi coverage area.
作者
杨刚刚
李方林
张雄华
Yang Ganggang;Li Fanglin;Zhang Xionghua(Xinjiang Institute of Geological Survey,Urumqi,Xiinjiang,830000,China;China University of Geoscience,Wuhan,Hubei,430074,China)
出处
《新疆地质》
CAS
CSCD
北大核心
2018年第3期309-314,共6页
Xinjiang Geology
关键词
东戈壁钼矿
弱胶结层
元素分布规律
活动态赋存形式
East Gobi Molybdenum Ore
Weak cementation layer
Element distribution
Mobile existence forms
