新疆谢米斯台布拉特地区中—基性火山岩及其矿化特征
发布时间：2018-10-12 06:28
【摘要】：谢米斯台地区位于新疆西准噶尔北缘。本文在前人研究的基础上,以野外地质考察、岩相学、矿相学、地球化学和金属矿物电子探针分析等方法为支撑,查明谢米斯台布拉特地区自然铜矿化中-基性火山岩的地质、地球化学特征,初步探讨其形成时代、岩石成因和形成构造环境,为探讨谢米斯台地区古生代构造演化提供新的证据;查明自然铜矿化特征和金属矿物成分特征,初步探讨自然铜成因,找矿前景和找矿标志,为区内进一步找矿勘查工作提供参考。论文取得以下主要成果:1、通过野外地质考察及项目内部获得的区内酸性火山岩、次火山岩年龄,初步推测谢米斯台地区自然铜矿化中-基性火山岩形成于晚志留世或晚志留世之前。2、研究区基性火山岩MgO含量为(4.32%～7.23%),Mg#值为49.59～58.38,FeOT/MgO 比值为 1.57～2.24;中性火山 MgO 含量为(3.84%～6.08%),Mg#为 56.57～62.45,略高于基性火山岩,FeOT/MgO比值为1.32～1.51,略低于基性火山岩。两者都属于钙碱性系列岩石,具有较高的Na2O+K2O和Al2O3值,相对富铁贫镁,富集Ba、Sr和Pb,亏损Nb、Ta和Ti等元素。3、研究区中-基性火山岩形成于俯冲背景下的大陆边缘弧环境,主要经历了单斜辉石的分离结晶作用、大陆地壳物质的混染和俯冲流体的交代。4、研究区矿化中-基性火山岩蚀变较强,蚀变类型多样,火山热液脉发育。自然铜矿化主要发育于这些蚀变的中-基性火山岩及其中的晚期热液脉中,矿化与火山热液热液作用有关,热液作用可以分为3个阶段。5、布拉特地区自然铜矿化中-基性火山岩规模相对较小,可以作为品位高、埋藏浅、易采选的小型铜矿床进行勘查开发,具有一定的经济和社会效益。区内自然铜找矿标志:a蚀变及脉体标志;b颜色呈绿灰色,气孔杏仁体小;c石英绿帘石团块。
[Abstract]:The Shermisi area is located in the northern margin of Xinjiang West Junggar. On the basis of previous studies, based on field geological investigation, petrography, mineralogy, geochemistry and electron probe analysis of metallic minerals, this paper investigates the geology of the natural copper mineralization of the Meso-basic volcanic rocks in the Shemistibart area. Geochemical characteristics, preliminary study of its forming age, petrogenesis and tectonic setting provide new evidence for the paleozoic tectonic evolution in the Semistii area, and find out the characteristics of natural copper mineralization and metallic mineral composition, and provide new evidence for the discussion of the evolution of Paleozoic structures in the Shemishitai area. The origin of natural copper, the prospecting prospect and the prospecting marks are discussed preliminarily, which provides a reference for further prospecting and exploration in the area. The main achievements of this paper are as follows: 1. The ages of acid volcanic rocks and subvolcanic rocks in the area obtained through field geological investigation and internal project. It is inferred preliminarily that the natural copper mineralization in the Shermisitai area was formed in the middle to basic volcanic rocks during the late Silurian or before the late Silurian. 2. The MgO content of the basic volcanic rocks in the studied area is (4.32 ~ 7.23%), the Mg# value is 49.59 ~ 58.38%, the FeOT / MgO ratio is 1.572.24, and the neutral volcanic MgO is 1.572.24. The content of FeOT/MgO is (3.84 ~ 6.08%), Mg# is 56.57 ~ 62.45, which is slightly higher than that of basic volcanic rock, and the FeOT/MgO ratio is 1.32 ~ 1.51, which is slightly lower than that of basic volcanic rock. Both belong to calc-alkaline series rocks, with high Na2O K _ 2O and Al2O3 values, relatively rich in iron and magnesium, rich in Ba,Sr and Pb, depleted in elements such as Nb,Ta and Ti. 3. The meso-basic volcanic rocks in the study area were formed in the continental margin arc environment in the subduction setting. It mainly experienced the separation and crystallization of clinopyroxene, the mixing of continental crustal materials and the metasomatism of subduction fluids. The natural copper mineralization is mainly developed in these altered meso-basic volcanic rocks and their middle-late hydrothermal veins, and the mineralization is related to the volcanic hydrothermal process. The hydrothermal process can be divided into three stages. 5. The natural copper mineralization in Blatter area is relatively small in scale and can be used as a small copper deposit with high grade, shallow burial and easy to be mined. It has certain economic and social benefits. The natural copper prospecting marks in this area are as follows: a alteration and vein marker; b color green-gray, small stomatal almond body; c quartz green coronite mass.
【学位授予单位】：西北大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P588.14;P618.41
，
本文编号：2265118
[Abstract]:The Shermisi area is located in the northern margin of Xinjiang West Junggar. On the basis of previous studies, based on field geological investigation, petrography, mineralogy, geochemistry and electron probe analysis of metallic minerals, this paper investigates the geology of the natural copper mineralization of the Meso-basic volcanic rocks in the Shemistibart area. Geochemical characteristics, preliminary study of its forming age, petrogenesis and tectonic setting provide new evidence for the paleozoic tectonic evolution in the Semistii area, and find out the characteristics of natural copper mineralization and metallic mineral composition, and provide new evidence for the discussion of the evolution of Paleozoic structures in the Shemishitai area. The origin of natural copper, the prospecting prospect and the prospecting marks are discussed preliminarily, which provides a reference for further prospecting and exploration in the area. The main achievements of this paper are as follows: 1. The ages of acid volcanic rocks and subvolcanic rocks in the area obtained through field geological investigation and internal project. It is inferred preliminarily that the natural copper mineralization in the Shermisitai area was formed in the middle to basic volcanic rocks during the late Silurian or before the late Silurian. 2. The MgO content of the basic volcanic rocks in the studied area is (4.32 ~ 7.23%), the Mg# value is 49.59 ~ 58.38%, the FeOT / MgO ratio is 1.572.24, and the neutral volcanic MgO is 1.572.24. The content of FeOT/MgO is (3.84 ~ 6.08%), Mg# is 56.57 ~ 62.45, which is slightly higher than that of basic volcanic rock, and the FeOT/MgO ratio is 1.32 ~ 1.51, which is slightly lower than that of basic volcanic rock. Both belong to calc-alkaline series rocks, with high Na2O K _ 2O and Al2O3 values, relatively rich in iron and magnesium, rich in Ba,Sr and Pb, depleted in elements such as Nb,Ta and Ti. 3. The meso-basic volcanic rocks in the study area were formed in the continental margin arc environment in the subduction setting. It mainly experienced the separation and crystallization of clinopyroxene, the mixing of continental crustal materials and the metasomatism of subduction fluids. The natural copper mineralization is mainly developed in these altered meso-basic volcanic rocks and their middle-late hydrothermal veins, and the mineralization is related to the volcanic hydrothermal process. The hydrothermal process can be divided into three stages. 5. The natural copper mineralization in Blatter area is relatively small in scale and can be used as a small copper deposit with high grade, shallow burial and easy to be mined. It has certain economic and social benefits. The natural copper prospecting marks in this area are as follows: a alteration and vein marker; b color green-gray, small stomatal almond body; c quartz green coronite mass.
【学位授予单位】：西北大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P588.14;P618.41
，
本文编号：2265118
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