龙头山金矿构造控矿作用及找矿方向

龙头山金矿的主要矿体受火山机构构造、断裂构造和雏形断裂构造三种成矿构造控制。火山机构构造控制了产于火山与围岩的接触带部位的火山岩型金矿,该类金矿以Ⅸ号矿体最为典型,表现为矿体围绕火山机构引起的塌陷式断裂产出,矿体的形态和品位变化受火山机构构造发育程度的影响;断裂构造控制了产于泥盆系砂岩中的断裂裂隙充填型金矿,以Ⅰ号矿体最为典型,表现为矿体沿NW向断裂分布,其产状与断裂一致,向SE方向侧伏明显;雏形断裂控制了矿区南部含金富矿体的就位,表现为矿区花岗斑岩南部的富矿体沿近EW向断续展布。矿体的形成与定位都离不开这三种控矿构造,因此在靠近火山机构一定范围内,向SE方向的深部及在已知富矿体的东西两侧具有较好的找矿前景。

Structure ore control and prospecting direction of Longtoushan gold deposit

The main orebodies of Longtoushan gold deposit are controlled by three kinds of metallogenic struc-tures,namely volcanic edifice structure,fracture structure and embryonic fracture structure.Volcanic edifice structure controls the volcanic rock type gold ores which occur in the contact zone between volcano and wall rocks,and orebody IX is the most typical one among this type of gold deposits.It often manifests as collapse fracture occurrence caused by volcanic edifice surrounded by orebodies.The shape and grade of the orebodies are influenced by the development of volcanic edifice.The fracture structure controls the fracture-fissure fill-ing type gold ores occurred in Devonian sandstone,and orebody I is the most typical one.It often manifests as distribution of orebodies along NW-trending fracture,and its occurrence is consistent with the fracture, obviously pitching towards southeast.Embryonic fracture controls the emplacement of gold-bearing ore shoot in southern mining area,and it manifests as interrupted distribution of ore shoots along the east-west direction at the south of granite porphyry in the mining area.The formation and location of the orebodies are closely related to the three kinds of ore-controlling structures.Therefore,within a limited peripheral area of the volcanic edifice,the prospecting potential is favorable in the deep part of southeastern area and on the east and west side of the known ore shoots.