喀麦隆洛比铁矿地质构造特征及找矿方向

Geological Structure Features and Prospecting Direction of the Lobe Iron Deposit,Cameroun

喀麦隆洛比铁矿床位于喀麦隆克里比地区强烈变质的太古宙变质岩系之中,区域上位于一向斜两背斜褶皱构造的东侧背斜的西翼。通过野外地质调查、探矿工程及室内资料整理,查明洛比铁矿主矿带长约15 km,宽约400 m,矿体厚度约60 m。主矿体呈一复向斜构造,轴面向西倾斜,脊线北北东向。本文重点对矿区地质构造特征进行了解析,研究表明洛比铁矿控矿构造为多期构造作用叠加形成的复向斜构造,核部为磁铁石英岩,两翼为角闪岩、片麻岩,磁铁石英岩内部也发生了强烈的早期褶皱变形,形成面状构造、线状构造。按照复向斜核部控矿,圈定了最有利的成矿位置,为喀麦隆洛比铁矿床下一步找矿奠定了基础。

Cameroun Lobe iron deposit lies in the Archean strong metamorphic area,structurally located in the west limb of the east anticline which belongs a one-synclinal-two-anticlinal mulitple fold.The study on the field geological investigation and exploration engineering as well as some indoor data shows that the length of the main ore-bearing belt is about 15 km,the width is 400 m and the average thickness is about 60 m.The main orebody is a composite syncline structure,the axial plane dips to the west with NNE direction ridge line.The authors analyse the structure of this deposit and suggest that the ore-control structure is composite syncline structure which is resulted from the superimpositions of multiple geological structures,the magnetite-quartzite occurs in the core part with the amphibolite and gneiss in two wings.The early intense fold deformation happened in the core part of the magnetite-quartzite,which forms planar structure or linear structure.Based on the composite syncline core ore-control regularity,the most fovorable mineralization position is delineated,which lays a foudation for the next geological prospecting in the Cameroun Lobe Iron deposit.