大兴安岭阿尔山大山多金属矿区控矿断裂有限应变测量与分析  

Finite strain measurement and analysis of ore-control fault in Dashan polymetallic deposit,Aershan mountain,Daxing′anling area

作　　者：解惠[1] 侯立平[1] 吕杜[1] 农建刊 王治颖 李艳阳[1] 

机构地区：[1]四川省冶金地质勘查院,四川成都610051

出　　处：《地质找矿论丛》2016年第2期228-235,共8页Contributions to Geology and Mineral Resources Research

基　　金：国土资源部内蒙古兴安盟阿尔山地区1:5万区域矿产地质调查项目(编号:NMKD2006-08)资助

摘　　要：文章通过对大山多金属矿区的主控矿断裂的三维应变测量分析,确定了大山多金属矿区主干控矿断裂其北东段为右行剪切兼逆冲性质的韧性剪切带,带内显微构造变形机制以粒内滑动、位错为主;确定了大山多金属矿区晚侏罗世(主构造期)的应变缩短主轴方位,也间接取得这次运动对应的σ1(最大主应力)、σ2(中间主应力)、σ3(最小主应力)的方位分别为345°∠18°、247°∠9°、150°∠72°。对部分韧性剪切带来说,若在野外能够直接利用面状和线状组构要素确定主应变轴的方向,简易应变测量方法可行。大山地区今后的找矿远景区段是上奥陶统裸河组二段内的的次级剪切断裂是下一步寻找多金属矿的远景区段,次级剪切断裂与近EW向张节理交汇处是重点找矿靶区。矿床类型除了夕卡岩型、隐爆角砾岩型外,应重视剪切带型。Finite 3D strain measurement and analysis of ore-control fault in Dashan polymetallic deposit are carried out and dextral and reverse movement of ductile shear zone in northeast sector of the major ore-control fault in Dashan polymetallic deposit is determined.Within the zone microscopic structural strain is dominated by intrograin sliding and displacement.The 3D strain measurement determines directly orientation of the strain shortened major axis during the main tectonic period of Late Jurassic period in the Dashan polymetallic area and indirectly the orientation of the maximum main stress σ_1,the intermediate main stress σ_1,and the minimum main stress σ_3 corresponding to the movement.The stress orientation is 345°∠18°、247°∠9°、150°∠72°respectively.In field the main strain axis can be determined by measurement of the planer and linear elements It is easy and practical.The future prospecting targets in the area are the sub-scale shearing fault within Luohe formation of Upper Ordovician Series,intersection of the sub-scale shearing fault and roughly EW tensile joints and the latter should be focused.In addition to skarn type and crypto-blast breccia type polymetallic deposit attention should be paid to shear zone type deposit in fiture prospecting.

关 键 词：大山多金属矿 有限应变测量 主构造期 成矿预测 内蒙古 

分 类 号：P613[天文地球—矿床学] P618.4[天文地球—地质学]