论武都复合型斜叠弧形构造及其控矿作用

摘 要　 武都弧形构造构成西秦岭地区主要构造格局?它是由礼县弧、武都弧、文县弧和白 马弧构成的一个复合型斜叠弧形构造系统?其弧顶呈 NE 向斜叠?东翼向 NE 向收敛归并?西 翼向 NW 向散开。其主要活动时期为燕山晚期—喜马拉雅期?是在 SN 向挤压构造应力场作 用下?并受到东部 NE 向龙门山构造带和西部康藏地块的边界约束作用?地壳表层发生由北 向南的不均匀推挤而形成的。它对区内金矿床具有重要的控制作用?表现出明显的构造成矿 专属性?且具有显著的弧顶控矿的特点。

STUDY ON THE COMPOUND JUXTAPOSED ARCUATE STRUCTURE SYSTEM IN WUDU REGION AND ITS CONTROLLING TO THE GOLD MINERALIZATION

The arc structure located in Wudu Wenxian region is a complex compound juxtaposed structure system and it control the major tectonic framework of West Qinling. The arc structure system are constituted by Lixian arc, Wudu arc, Wenxian arc and Baima arc. It takes the form of juxtaposed arcuate structure toward NE orientation, with east wing convergenced toward NE orientation and west wing scattered toward NW orientation. The major tectonic activity period was late Yanshanian Himalayan stage. It took place for the surface of earth crust to push with inhomogeneous from north to south by the tectonic stress field of SN orientation compressive, as well as tectonic movement. It is limited by the boundary condition of NE orientation Longmen Mountain tectonic belt on the east side and Xizang mass on the west side. On the other hand, the arcuate structure system takes an important role of controlling to the gold deposits in this region, especial the arcuate fault systems are the most important ore controlling structural condition. It is revealed that there are different ore controlling for the different location of the arcuate and takes obviously arc top ore controlling.