张宣幔枝构造与金多金属矿化———进展、规律、问题及找矿方向

Zhangjiakou—Xuanhua Mantle Branch Structures and Gold-Polymetallic Mineralization—Progress,Patterns,Problems and Directions for Mineral Search

地幔热点及幔枝构造在古张宣幔枝构造寻找金多金属成矿系统取得了较大的成果,系统总结了张宣幔枝构造的组成,以及与主要金矿床在空间、时间以及成因联系,总结其产出规律,并指出其存在问题,以及优选的找矿方向。研究表明,张宣幔枝的核部主要是岩浆-变质杂岩,与大中型矿床与其在空间上存在着密切的关系。此外,岩浆-构造热事件对矿床的控制明显,主要表现在:(a)韧性剪切带对矿床展布控制明显;(b)碱性—偏碱性岩浆岩可能为区域金矿床的热源。此外,区域金矿床的成矿具有明显叠加成矿的特征,主要成矿期为:400~350 Ma和150~130 Ma。成矿的动力机制是幔枝构造,其成矿物质来源来自深源,区域金矿床主要赋存在其核部,银多金属矿床多赋存在其外围。结合物化探与找矿标志,葵花村—黄土梁—温泉、金家庄—后沟、中山沟—水泉沟—东坪、水晶屯—小营盘—张全庄、下双台—下两间房等5处找矿潜力巨大。

The mantle hot spot and mantle branch tectonics have made great achievements in the search of gold-polymetallic mineralization system in the ancient Zhangjiakou-Xuanhua mantle branch tectonics.This paper systematically summarizes the composition of Zhangxuan mantle branch tectonics,as well as the spatial,temporal and genetic connection with the main gold deposits,summarizes its output law,and points out its problems and the preferred direction of mineralization search.The study shows that the nucleus of Zhang-Xuan Mantle Branch is mainly magmatic-metamorphic heterogeneous rocks,and there is a close relationship between it and large and medium-sized deposits in space.In addition,the magmatic-tectonic thermal events have obvious control on the deposits,mainly in(a)the ductile shear zone has obvious control on the spreading of the deposits;(b)the alkaline-alkaline magmatic rocks may be the thermal source of regional gold deposits.In addition,the mineralization of regional gold deposits has obvious characteristics of superposition mineralization,the main mineralization periods are:400~350 Ma and 150~130 Ma.The dynamic mechanism of mineralization is mantle branch tectonics,and the source of mineralized material comes from deep source,the regional gold deposits are mainly in its core,and the silver polymetallic deposits are mostly in its periphery.Combined with the physical and chemical exploration and mineral search signs,five places,including Kuihua Village—Huangtuliang—Hot Spring,Jinjiazhuang—Hougou,Zhongshangou—Shuiquangou—Dongping,Crystal Tun—Xiaoyingpan—Zhangquanzhuang,and Xia Shuangtai—Xiaoliangjianfang,have great potential for mineral search.