摘要
金矿带位于胶北隆起的西北部,栖霞复背斜北翼。矿床类型为蚀变岩型和石英脉型。金矿严格受NE、NNE向构造控制。金矿床最佳元素组合是:Au、Ag、Te、Bi;Au、Ag、Cu、As、Pb。找矿指示元素为:Au、Ag、Te、Cu、Pb、Zn、Sb、Mn、Ba等10种。Au与Ag、As、Te、Bi、Cu密切相关,Au与Ag、As、Te相关系数接近1。矿体异常按三级浓度带圈定,出现三个浓度带的元素有:Au、Te、Ag、Cu、还有Zn、Mo。外带与蚀变带空间展布基本一致,内带反映矿体空间位置。矿体元素轴向分带自上而下是:Sb、As、Ag、Pb、Bi、Cu、Se、Te、Au、Zn、Mn、Ba、Mo。矿体不同标高元素对比值(As×Ag)×100/Mn,矿体头部比值>2;矿体中部比值>0.5,<2;矿体尾部比值<0.5。矿体头尾晕判别函数分带指标,判别函数是:y=0.0685Ln(Ag×As)-0.0182Ln(Au×Te)-0.0203LnCu-0.1046LnMn。判别临界值Yc=-0.4960,当判别函数Yc大于或小于-0.4960时,分别为矿体头部和尾部指标。金矿床地球化学异常模式,异常元素在矿体空间有明显浓度分带和垂直分带。异常受构造控制,并与构造方向一致,且呈带状分布。矿体头部元素:Sb、As、Ag;近矿指示元素:Au、Te、Bi、Cu、Pb;矿体尾部指示元素:Mo、Ba、Mn、Zn。金矿原生晕可以有效地直接圈定破碎蚀变带及脉体含矿富集地段,以及寻找深部盲矿体和判断矿体剥蚀程度。
The gold ore zone is located in the north-west of the Jiaobei Uplift and the north flank of the Qixia Anticlinorium. The depositions can be classified into two types, namely, the alteration rock type and the quartz vein type, which are highly controlled by the NE trending and NNE-trending structures.The most favourable combinations of the gold deposits are: Au, Ag, Te, Bi; Au, Ag, Cu, As, Pb. There are ten indicator elements for gold prospecting, ie. Au, Ag, As, Te, Ca, Pb, Zn, Sb, and Ba. Au is closely related to Ag, As, Te and Cu, and the correlation coefficient between Au and each of Ag, As, and Te is close to 1.The geochemical anomalies of orebodies can be delineated in the light of three concentration zones with respect to the elements of Au Te, Ag, Cu, Zn and Mo. The spatial distribution of the outside zone is almost the same as that of the alteration zone. The inside zone corresponds spatially to the orebody. The distribution of the element within and around the orebody is featurid by a vertical zoning and it goes like this: Sb, As, Ag, Pb, Bi, Cu, Se, Te, An, Zn, Mn, Ba and Mo (from above to below ). The (As×Ag)x100/Mn ratio in the orebody changes with the elevation, being>2, 0.5-2 and<0.5 for the upper, middle and lower parts of the ore body, respectively. The Zoning indexed discriminant function of the frontal halo and the tail halo of the ore body is Y=0.0685Ln(AgxAs)-0.0182Ln (AuxTe)-0.0203LnCu-0.1046LnMn, with the critical value Ye being '-'0.4960. For the frontal halo, Yc is greater than'-'0.4960 whereas the tail halo has Yc less than'--'0.4960.In terms of our geochemical anomaly pattern of the gold deposits, the distributions of elements are obviously in concentration zoning and vertical zoning. The anomalies are controlled by the structure having the same orientation with it and distributed in zonation. The elements ocurring on the top of the ore bodies are Sb, As and Ag. The indicator elements near the ore bodies are Au, Bi, Cu and Pb. The indicator elements in the tail zone of the ore bodies are Mo, Ba, Mn, and Zn.The primary halo of the geochemicaJ anomalies can be used to delineate effectively and directly the crush-alteration zone and veins of gold-concentrated mineralization, to search for blind orebodies in the deep and to determine the erosion level of the known orebodies.
出处
《山东地质》
1990年第2期45-61,共17页
Geology of Shandong
