南秦岭丁—马金汞锑矿带成矿规律与找矿前景

南秦岭丁（家山）—马（家沟）金汞锑矿带位于华北地台与扬子地台两大构造单元的过渡部位，镇安—板岩镇深大断裂南侧，该矿带金汞锑成矿条件有利，分布有龙山、丘岭、腰俭等大中型金矿床和西坡岭、丁家山、石家山等中小型汞锑矿点。丁—马金汞锑矿带金汞锑矿化是同一空间（构造地质背景）下物理化学条件变化的演化结果，显示出成矿继承性和阶段性的演化特点，是一个成矿组合演化系列，在时空分布上有明显规律性；背斜轴部及两翼受强烈的挤压作用发育密集裂隙、节理及近EW向挤压破碎带（剪切带），这些地段是成矿的有利部位，直接控制着区内内生金属矿产的空间分布，NE向断裂为本区主要控矿构造。根据已有资料和找矿实践，通过进一步探讨丁—马金汞锑矿带成矿规律，分析找矿前景，以期对该矿带内进一步勘查找矿提供有益参考。研究认为，该矿带成矿条件较好，在古楼山、郭家山和杨家岭等尚未开展系统勘查的地区，以及汞锑老矿区的纵深、侧翼和已知矿体深部，找矿潜力均较大。

Metallogenic Regularity and Prospect Analysis of Ding-Ma Au-Hg-Sb Deposit in South Qinling Orogen

The geotectonic environment of the gold-mercury-antimony ore belt in the South Qinling Dingjiashan-Majiagou is located in the transitional part between the north China platform and the Yangtze platform.The south side of the Zhen-Ban deep fault is favorable for metallogenic conditions，north wing of Jinjiling compound syncline，and it has been a mining area for mercury-antimony since ancient times，combined with the above characteristics，the geotectonic environment of the gold-mercury-antimony ore belt is one of the important mineral resources in China. At present seventy-five gold bodies，more than one hundred mercury and antimony ore body has been found in the gold-mercury-antimony ore belt in the South Qinling Dingjiashan-Majiagou.Up to now it has been reached supersize，so it became one of the few supersize gold and poly-metallic deposit in Qinling area.The mineralized present mainly in NE-trending and NW-trending fault zone，and then it exist in near NW-trending interlayer shear fracture zone.There are Hg-Sb deposits in the mid-east side of the ore zone(Dingjiashan-Majiagou)，and equally further enrichment of gold and antimony in the western(Guloushan-Jinloushan).The metallogenic belt was divided into seven ore sections from east to west，according to the characteristics of the relativety concentrated mineralization.It respectively are Shijiashan，Dingjiashan，Xipoling，Jinlongshan，Yaojian，Qiuling，and Guloushan.The Au-Hg-Sb mineralization is belong to the same metallogenic series，it has horizontal and vertical zoning characteristics in space，by contrast there is a close symbiotic relationship，and at the same time exist in different strate of the belt.The wall rock alteration closely related to minrealization is mainly silicification and carbonation.When pyritization，arsenopyrite and weak silicification occur simultaneously，which indicates gold mineralization enrichment or the existence of gold orebodies.Jasper veins filled in tensional fault zones，and again broken breccia，stibnite and cinnabar mineralization occur，accompanied by strong silicification and calcification.The metallogenic age is the early Late Mesozoic，which is the metallogenic response of the collisional orogeny in the South Qinling Mountains.The Au-Hg-Sb mineral desposit is made up of the effect of basin-mountain transformation under the tectonic system and late tectonic magmatism，it formed during the transition form compressional to extensional tectonic mechanisms.The formation of Hg and Sb was later than that of Au，so the metallogenic age(phase) extists successively and succession relation.The Au-Hg-Sb ore bodies are controlled by tectonic lithology，the SN-trending compressive stress in Indosinian period formed nearly EW-trending tight anticline folds，and the dome structure formed by overlapping the NE-trending wide and gentle anticline folds in Yanshanian period formed the main structural framework in this area.Joints and nearly EW-trending compression fracture zones （shear zones） developed intensively on the axis and wings of the anticline under intense compression are favorable sites for mineralization，which often directly control the spatial distribution of endogenous metal minerals in the area.The NE-trending faults are the main ore-controlling structures in the area.The other NW and SN trending fault structures have poor ore-bearing property.The main ore-bearing structures in Dingjiashan，Jinlongshan and Qiuling ore sections are NE trending fracture zones.The metallogenic condition of the Ding-Ma ore belt is better ，such as Guloushan,Guojiashan and Yangjialing and other areas without systematic exploration，it has great prospecting potential in the depth and flanks of old mercury mines and in deep parts of known ore bodies.