【作者】 焦骞骞；

【导师】 邓江红；

【作者基本信息】 成都理工大学 ， 矿产普查与勘探， 2010， 硕士

【摘要】 绿春-墨江地区位于云南省西部,属“三江成矿带南段”,处于哀牢山造山带与昌都-思茅盆地的交界处。研究区内地层发育较全,从志留系至白垩系皆有分布,尤以中生界三叠系为甚,其中歪古村组是重要的含矿层;岩浆岩以岩脉、岩枝、小型岩株等零星出露,岩性以浅成中-酸性为主,次有基性、中性,其中煌斑岩、酸性斑岩与金矿关系密切;变质岩仅见于志留系、部分围岩和断裂带中。区内构造复杂,自东向西依次由洛恩断片、牛孔-黄草岭断裂(九甲-安定断裂)、牛孔断片、大头断裂、大水沟断片、大掌-尔牙断裂、坝溜断片、阿墨江断裂推覆叠置组成哀牢山造山带前缘推覆构造带。区内典型矿产有金矿、铜矿、锰矿、煤矿等,前人化探工作还发现有辰砂、钛、铬钒、铅锌等异常和高含量点。在不同断片内成矿地质背景不同,矿产种类也有所差异。通过典型矿产特征分析及区域对比总结控矿因素。牛孔金矿床位于牛孔断片中,根据前人工作及本次实地考查,由矿体产出位置、岩浆岩特征、围岩蚀变、矿石特征等判断,为一小型构造破碎带蚀变岩型金矿床。控矿因素有:(1)NW向-近EW向断裂,尤其在与SN向断裂交汇部位;(2)断层及附近有中酸性斑岩和煌斑岩侵入;(3)矿体赋存于歪古村组中。类比哀牢山金矿带金矿,成矿时期可能为燕山晚期-喜山早期。由于不具有类似于老王寨金矿的双矿源层,成矿物质可能主要来自于燕山晚期-喜山期小规模侵入的中酸性斑岩与煌斑岩,难以形成大型金矿。因此虽有寻找金矿的潜力,但规模有限。迷那铜矿位于坝溜断片内上三叠统歪古村组浅灰色砂岩中,由矿体、矿石特征判断为一砂岩型铜矿。根据矿区地质特征及控矿因素推断该矿形成经历了两个阶段:三叠纪时铜沉积形成初始含矿层,后期NNW向断裂活动提供热液使铜质进一步富集形成矿化点(体)。另外在该断片内上三叠统还存在多处铜化探异常,因而具有较大的找矿潜力。巴甫锰矿产于牛孔断片内上三叠统歪古村组厚度较大的含锰岩系中。根据矿体、矿石特征判断为一风化淋滤型锰矿。该矿的形成也经历了两个阶段,三叠纪时沉积形成含锰的岩系,但并未成矿,真正形成矿体应该是在第四纪。由于原始含矿层中锰质含量低,后期成矿时条件特殊,因此该类矿产前景有限。区内的两个煤矿点分别产在大水沟断片内上石炭统下密地组和中下二叠统仙人洞组中,另外在上二叠统羊八寨组,上三叠统挖鲁八组和麦初箐组中均可见到煤线。但从区域上看,成煤条件并不好,找矿潜力不大。研究区内的控矿因素有以下特点:(1)上三叠统,尤其是歪古村组对矿产控制作用明显,显示出区域(“三江成矿带”)特征;(2)构造控矿明显,但不同断片内控矿断层方向不同,在坝溜断片内受近SN向-NW向断层控制,其它几个断片受NW向-近EW向控制,表明构造-成矿作用的阶段性和分区性;(3)中酸性浅成-超浅成岩浆、幔源偏碱性煌斑岩浆的叠合作用对金矿的富集和成矿起到了明显的促进作用。通过对控矿因素分析和归纳,探讨了构造、沉积、岩浆及变质地质作用与成矿的关系。最后给出两个最有潜力找矿区,牛孔断片东部歪古村组NW向-近EW向断裂发育区最有利于寻找金矿,坝溜断片东部三叠系内最有利于寻找砂岩铜矿;给出三个潜力找矿区,坝溜断片西侧上二叠统NW向断裂发育区和洛恩断片有找金的潜力,沿牛孔-黄草岭断裂有寻找热液型铜矿的潜力;还给出了铜砷矿、煤矿和锰矿的找矿远景区。更多还原

【Abstract】 The strata is relatively abundant in Luchun-Mojiang Region, which is located in the western Yunnan Province, southwestern China, part of the“south Sanjiang metallogenic belt”, at the junction of Ailaoshan Orogen and Changdu-Simao Basin, including from the Silurian to Cretaceous,especially the Triassic, and the Waigucun Formation of Triassic is an important ore-bearing strata. Magmatic rocks scatters, as apophyse,dike and small-scale stock,among which intermediate-acidic hypabyssal rocks are dominated and intermediate,mafic rocks are subordinate. The acidic porphyry and lamprophyre play an important role in the formation of gold deposit.The distribution of metamorphic rocks is only in the Silurian strata, wall rocks, fault zones.Study region is front-edge faults of Ailaoshan orogen which consist of Luoen Slice,Niukong-Huangcaoling Fault, Niukong Slice, Datou Fault, Dashuigou Slice, Dazhang-Erya Fault, Baliu Fault and Amojiang Fault from east to west.The typical minerals are gold, copper, manganese, coal, etc., and there are some cinnabar, titanium, chromium and vanadium, lead and zinc anomalous area and high points which were found by previous geochemical work. There is diversity of the geological setting of ore-forming process in differert slice, so do the mineral types.Niukong gold deposit is located in Niukong Slice.According to previous work and field survey, based on the location of orebodies, magmatic characteristics, wall rock alteration and ore characteristics , it is judged as a tectonoclastic zone altered rock type Gold deposit. The ore-controlling factors are:NW to nearly EW extending fault,especially the convergence zone with the SN extending fault; tectonoclastic zone intruded by the intermediate-acidic porphyry and lamprophyre;the Waigucun Formation of the Triassic.By contrast to the Ailaoshan gold belt,it is inferred that the formation of the deposit may be in the late Yanshan stage to early Himalayan stage.Mina copper mine is located in Baliu Slice,and ore bodies are bound to grey sandstone in Waigucun Formation.So it is judged as a sandstone copper ore.According to the characteristic of ore district and the ore-controlling factors,it is inferred the formation of deposit experience two phase——forming the primary ledge in Triassic;hydrothermal that come from NNW extending fault having the copper enriched and forming ore bodies.Bafu manganese mine is located in Niukong Slice,and the ore body exist in the relatively thick layers which contain manganese in Waigucun Formation.Based on the characteristic of the ore body and ore,it is regard as a weathering-leaching manganese mine.The formation of deposit also experience two phase——forming the primary ledge in Triassic; forming ore bodies in Quaternary.Two coal mine points located in Dashuigou Slice,and the seam exist in Xiamidi Formation and Xianrendon Formation,respectively. Moreover, Yangbazhai Formation, Waluba Formation and Maichuqing Formation all possess coal lines.The characteristics of ore-controlling factors in study region are:minerals are obviously controlled by the Up Triassic Series, especially the Waigucun Formation, which show the areal geology——Sanjinag metallogenic belt feather; minerals are controlled by nearly SN extending to NW extending fault in Baliu Slice, by NW extending to nearly EW extending fault in others,which show the tectonic ore-formation is periodical and divisional; hypabyssal and ultra-hypabyssal intermediate-acidic magma and the mantle-derived alkaline lamprophyre facilitate the enrichment and formation of gold deposit.Based on the analysis of ore-controlling factors, the relationship between mineralization and geological processes is discussed. In the end,it is recommended that NW to nearly EW extending fault in Waigucun Formation in Niukong Slice and the Triassic in Baliu Slice are two most potential prospecting area for gold ore and copper ore,respectively; Luoen Slice and NW extending fault in Up Permian Series in Baliu Slice are two potential prospecting area for gold ore,and on both sides of Niukong Fault are potential prospecting area for copper ore.Moreover, perspective area of copper arsenic ore,coal and manganese ore are also recommended.更多还原