浅析胶莱盆地边缘层间滑动断层构造及其控矿机制

层间滑动断层构造产出于胶莱拉分盆地边部莱阳组砾岩与下伏下元古界荆山群变质岩系的不整合面上 ,是胶莱盆地东北缘蓬家夼和发云夼层间滑动角砾岩型金矿化的主要部位。层间滑动断层是在中生代白垩纪期间中国东部古板块和郯庐断裂构造活动造成的区域大地构造背景下 ,在胶莱走滑拉分盆地的形成过程中产生的。在层间滑动断层由张性应力环境向挤压应力环境过渡过程中 ,源于地壳深部的金矿成矿流体 ,与大气降水混合形成工业金矿体 ,金矿化主要发生在构造角砾岩及碎裂岩的胶结物内 ,金矿化类型和强度具有明显的对称性。层间滑动断层以其产出于特定的部位、产状、成因及控矿机制的不同与其它伸展作用形成的断裂构造相区别。

A PRELIMINARY DISCUSSION ON THE INTERSTRATIFIED GLIDE FAULT AT THE MARGIN OF JIAOLAI BASIN AND ITS ORE-CONTROLLING MECHANISM

The interstratified glide fault is located in the contact zone of the sedimentary conglomerate of the Laiyang Formation and the metamorphosed rocks of the Jingshan Group at the margin of the Jiaolai apart basin, which is the important formation location of the interstratified glide breccia-type gold deposits, as in the Pengjiakuang and Fangyunkuang gold deposits. The formation of the interstratified glide fault is closely related to the formation of the apart basin with the regional tectonic background caused by the palaeo-plate movement in East China and the Tanlu fault during the Cretaceous. The ore-forming fluid coming from the deep crust is mixed with meteoric water to form the gold orebodies when the regional stress was transformed from extensional to compressive. Gold mineralization is mainly in the cement of structural breccia and the cataclastic rocks with an apparent symmetry. The interstratified glide fault is different from other extensional fault structures with respect to its specific location, occurrence, genesis and gold ore-controlling mechanism.;