玲珑花岗岩体的变形磁组构特征及其与金矿的关系

本文利用磁组构的方法对玲珑花岗岩体的磁组构特征及其与金矿的关系进行研究.玲珑岩体的磁化率各向异性度P的平均值为1.2872,具有典型的构造变形成因特点;磁面理围绕其西北侧的北截花岗闪长岩展布,倾角平缓;磁线理呈SW向近水平展布.玲珑岩体的变形磁组构的特征表明玲珑岩体的变形磁组构是由于后期侵入的北截郭家岭花岗闪长岩体侵入造成的.研究还发现除了断裂的控矿作用以外,位于玲珑岩体内部和边缘的金矿和磁化率各向异性间存在密切的空间对应关系.金矿往往位于磁化率各向异性度P值高的区域,而磁化率各向异性度P值低的区域金矿很少.

DEFORMATIONAL MAGNETIC FABRIC OF LINGLONG GRANITIC PLUTON AND ITS RELATIONSHIP WITH GOLD DEPOSITS

Magnetic fabric is a manifestion of anisotropy of magnetic susceptibility in rocks. Magnetic fabrics with different geneses have different features. In recent years, geologists have taken some effective researches on the emplacement and deformation features of granitic plutons using magnetic fabric analysis. The Linglong granitic pluton is in the north of the Linglong Composite Batholith in the Northwest of Jiaodong Pennisula, Shandong Province. The pluton has a close spacial relationship with gold deposits. The famous Jiaojia gold mine field and Linglong gold mine field are all in the margin of the pluton. The magnetic fabric features of Linglong granitic pluton and their relationship with gold deposits were studied. The mean degree of magnetic anisotropy is 1.2872, which means typical deformational genesis. The strike of magnetic foliations is circling Beijie granodiorite pluton with gentle dips; the magnetic lineations are almost horiziontal with NW trending. The research revealed that the deformational magnetic fabric is formed during the instrusion of Beijie granodiorite pluton; besides the control of faults to the gold deposits, the degree of magnetic susceptibility anisotropy and gold deposits have aslo a close spacial relationship. The gold deposits are located in places where the degree of magnetic susceptibility anisotropy is larger; otherwise, the gold deposits are very poor.