胶东招—平断裂带中段金矿床地质特征及找矿预测

发布时间：2018-02-07 15:23

  本文关键词： 矿床成因 找矿预测 地球化学特征 大尹格庄金矿 胶东　出处：《东华理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：胶东0.3%的国土面积却占有中国25%的黄金储量。绝大多数的金矿床发育在招平、焦家及三山岛三条成矿断裂带上。近年来,随着国民经济发展的需要,对黄金的需求量逐年加大,各大矿山企业不断开采生产,许多矿山面临着资源短缺。前人对该断裂带北段、南段开展过大量的野外地质调查及科学研究工作,而中段的研究程度相对较低。本文通过全面收集、整理和分析前人的研究资料,选择大尹格庄金矿井下切穿矿体上下盘的剖面为实例,系统的采取岩石样品,开展详细的岩相学、主微量元素分析等研究,通过对矿床地质特征、各个蚀变岩带岩石中元素的迁移富集规律、围岩蚀变地球化学特征进行详细的研究,总结招-平断裂带中段金矿床基本控矿特征,探讨矿床成因,在以上基础上选取招平断裂带中段作为研究区进行构造蚀变岩相填图和典型剖面的测量,划分构造蚀变岩带,确定蚀变标志,进行找矿预测。以期为下一步找矿提供科学线索。通过以上研究得出以下认识:(1)大尹格庄金矿严格受地层、岩浆岩、构造和围岩蚀变的共同控制,矿体产出于主断裂下盘的蚀变玲珑花岗岩中,上盘围岩为太古代胶东群变质岩。钾长石化、硅化和黄铁绢英岩化与金矿化关系密切。(2)大尹格庄金矿床各构造蚀变带不同蚀变强度的蚀变岩中常量元素迁移规律明显,说明了蚀变与矿化作用导致常量元素向矿体迁移富集。与大尹格庄金矿金矿化最为密切的是Fe2O3,K2O,Si O2,Ca O。REE的总量很高,轻、重稀土分异的现象较为明显,总体上可见轻稀土富集,配分曲线呈右倾型。Eu,Ce负异常较为明显。从断裂带弱蚀变至强蚀变过程中,ΣREE,LREE和HREE均有明显降低,且相应特征值表现出规律性的变化。Au与Ag,Bi,Cu,Hg,Zn的相关系数较高,Au-Ag-Bi-As-Cu-Hg-Ni-Pb-W-Zn是金成矿密切相关的指示元素组合。(3)大尹格庄金矿流体包裹体类型较多,且成矿温度总体分布在137℃-455℃区间内,流体类型总体为中温、中低盐度的Na Cl-H2O-CO2体系。(4)通过总结归纳前人硫同位素及氢氧同位素研究成果显示:大尹格庄金矿成矿物质不具深部硫特征。成矿流体以幔源初生水、岩浆流体及大气降水为主,并有少量变质水的加入。(5)通过地质填图及实测剖面得出:断裂面上下盘蚀变带宽度不一,总体特征表现为上盘宽度小于下盘宽度,且上下盘蚀变强度和破碎强度不一致,总体特征为下盘强于上盘。主断裂具明显的分带特征,岩石分带为:断层泥→黄铁绢英岩→绢云母化花岗岩→钾长石化花岗岩→弱片麻状含黑云母二长花岗岩→正常花岗岩;蚀变分带为未蚀变胶东群老地层→钾长石化→绢英岩化、硅化、黄铁矿化→钾长石化→未蚀变玲珑花岗岩。根据野外填图的资料及样品的测试分析,提出招远城南后疃西至道头镇西区段为成矿远景区。
[Abstract]:The land area of Jiaodong 0.3% accounts for 25% gold reserves in China. The vast majority of the gold deposits are developed in Zhaoping, Jiaojia and Sanshandao three ore-forming fault zones. In recent years, with the development of the national economy, the demand for gold has increased year by year. The major mining enterprises are constantly mining and producing, and many mines are facing a shortage of resources. The forefathers carried out a large number of field geological surveys and scientific research work on the northern and southern sections of the fault zone. The research level in the middle section is relatively low. Through collecting, arranging and analyzing the previous research data, this paper chooses the section of the upper and lower face of downhole cut ore body in Dayingezhuang Gold Mine as an example, and systematically adopts the rock sample. Through detailed petrography, principal and trace element analysis and so on, the geological characteristics of the deposit, the migration and enrichment of elements in the rocks of each altered rock belt, and the alteration geochemical characteristics of surrounding rock are studied in detail. This paper summarizes the basic ore-controlling characteristics of gold deposits in the middle section of the Zhao-Ping fault zone and discusses the genesis of the deposits. On the basis of the above, the middle section of the Zhaoping fault zone is selected as the study area to carry out structural alteration lithofacies mapping and typical profile survey, and to divide the structural altered rock belts. In order to provide scientific clues for the next prospecting, it is concluded that the Dayingezhuang gold deposit is strictly controlled by strata, magmatic rocks, structures and wall rock alteration through the above study. The orebody occurs in the altered Linglong granite in the lower face of the main fault, and the surrounding rock of the upper wall is the metamorphic rock of the Archean Jiaodong Group. The relationship between silicification and Huangtieranite is closely related to gold mineralization. (2) the law of the migration of major elements in alteration rocks with different alteration strength in each structural alteration zone of Dayingezhuang gold deposit is obvious. The results show that alteration and mineralization lead to the migration and enrichment of major elements to orebody, and the gold mineralization is most closely related to the gold mineralization in Dayingezhuang gold deposit. The total amount of Fe _ 2O _ 3K _ 2O _ K _ 2O _ 2 O _ 2O _ 2 Ca O. REE is very high, the phenomenon of light and heavy rare earth differentiation is obvious, and light rare earth enrichment can be seen on the whole. The partition curve shows the negative anomaly of right-dip type. The 危 REE LREE and HREE decrease obviously from the weak alteration to the strong alteration in the fault zone. The corresponding eigenvalues show regular variation. The correlation coefficient between au and AgAg-Bi-CuHg-Ni-Pb-W-Zn is higher than that of Ag-Ag-Bi-As-Cu-Hg-Ni-Pb-W-Zn, which is a closely related indicator element assemblage of gold mineralization. There are many fluid inclusions in Dayingezhuang gold deposit, and the metallogenic temperature is between 137 鈩，

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