满洲里-新巴尔虎右旗铜、钼、铅、锌、银带成矿条件与斑岩体含矿性评价标志

METALLOGENIC CONDITIONS AND CRITERIA FOR EVALUATING THE ORE POTENTIALITY OF PORPHYRY BODIES IN THE MANZHOULI-XINBAERHUYOUQI Cu,Mo,Pb,Zn AND Ag METALLOGENIC BELT

我们较充分地研究了本区主干断裂,次级构造、火山机构、多旋回火山岩浆活动以及热液蚀变的控矿作用,深入讨论了斑岩系列矿床的水平和垂直分带、矿化的岩石、矿物、地球化学(微量元素、同位素、流体包裹体等)标志,特别是发现并总结了稀土元素评价标志。对全区16个岩体及物、化探异常逐个比较判别,按含矿性分为四种类型,从而圈定了靶区。其中3个点已获生产验证,经济效益显著。

This area is a new remote border district. Some basic problems, especially those about the direction in mineral prospecting, should be answered. Based on regional geological investigations, typical deposit analysis and a lot of indoor work, the authors summarize and put forward 13 macroscopical and microscopical comprehensive criteria for mineral prospecting and assessment. They have fully studied the ore-controlling process of deep fractures, secondary fractures, volcanic edifice, polycyclie volcanic-magmatic activities and hydrothermal alteration as well as the horizontal and vertical zoning of porphyry deposits and petrological, mineralogical and geochemical (trace elements, stable isotopes and fluid inclusions) criteria for mineralization, especially the criteria for REE discrimination and evaluation.When the porphyry was altered, its ΣREE increased and Eu depletion appeared. Eu depletion is closely related to mineralization. For the alteration zones of the same type, the more marked the Eu depletion is, the better the mineralization will be. Based on ΣREE and alteration zoning, the burial depth of the orebodies can be inferred.Sixteen porphyry bodies and anomalies have been identified and compared, and then divided into 4 types according to their metallogenic prospects. Thus the targets have been outlined, of which 3 targets have been verified. The most optimum prospect area——Jiawula——has been confirmed to be a large Ag-Pb-Zn-Cu ore deposit.