玲珑似片麻状花岗岩构造岩相特征与玲珑金矿深部成矿预测

发布时间：2018-05-28 12:14

本文选题：胶东西北部 + 剪切相片麻状花岗岩　；参考：《中国地质大学(北京)》2017年硕士论文

【摘要】：胶东西北部地区广泛出露与金矿形成密切相关的中生代花岗岩。现阶段,地质工作者对胶东地区成矿花岗岩的研究主要采用单元-超单元的研究思路,随着胶东西北部金矿深部找矿工作的推进和构造地质学的发展趋势,本论文从花岗岩构造岩相的角度,选择玲珑似片麻状花岗岩作为研究对象,重点研究该类花岗岩的微观结构几何特征,主要包括岩体的面理展布特征、S-C组构和该结构构造的镜下及手标本几何形态。为构造岩相的应力分析提供了地质依据,具有重要的金矿勘查应用价值和地质科学意义。本人通过野外约5km2的区域地质调查,对研究区的岩体的面理构造现象进行了系统的观测,取得了较多的实测数据,编制面理展布轨迹图;在露头良好的观测点,采集标准的定向样品,进行室内的微观结构构造观测,并以九曲—大开头矿区48、50号脉为研究对象,进行井下中段地质填图与岩石地球化学测试分析,总结了矿床地质特征和深部成矿规律,提出深部隐伏矿体预测靶区,在这些工作的基础上,取得以下认识:1、岩体面理展布轨迹图显示,在岩体中部,面理大致呈圆形或椭圆形分布,进一步验证该类岩体岩浆在上侵过程中受区域挤压剪切应力形成了“岩浆核杂岩”隆起。2、建立剪切相似片麻状花岗岩三维几何构造特征判别标志,进行有限应变分析,利用弗林图解求得K值为1.54,岩浆是在NW-SE的伸展环境背景冷却固结成岩,最大主应力方位近于水平。3、岩浆期后热液蚀变岩石英流体包裹体均一温度、盐度测试结果表明,成矿流体具有中低温、盐度低的特点,并且盐度和温度呈现正向相关;包裹体压力计算结果表明,蚀变较强的部位压力比蚀变作用较弱的部位小,是压力、温度逐步下降的过程。4、建立深部成矿预测指标,厘定深部金矿富集带之间的距离约为200m,建立两条矿脉深部成矿预测模型示意图。其中50号脉矿体在深部探矿区中的预测深度大致在840m~1450m之间,而48号脉矿体在深部探矿区中的预测深度大致在1000m~1400m之间。
[Abstract]:The widespread outcrop in the north of Jiaobei area is closely related to the formation of Mesozoic granites. At present, the research of ore-forming granites in Jiaodong area mainly adopts the idea of unit superunit, along with the advance of deep prospecting and the development trend of tectonic geology of gold deposits in northwestern Jiaodong. In this paper, from the point of view of the tectonic facies of granite, Linglong granitoids are selected as the research objects, and the microstructural and geometric characteristics of the granites are mainly studied. It mainly includes the dissecting distribution characteristics of rock mass, S-C fabric and the microscopic and hand geometry of the structure. It provides geological basis for stress analysis of tectonic lithofacies and has important application value of gold exploration and geological scientific significance. Through the regional geological survey of 5km2 in the field, I have made systematic observation on the face structure phenomenon of rock mass in the study area, obtained more measured data, compiled the trace map of plane distribution, and made a good observation point in outcrop, Taking standard directional samples for indoor microstructure observation, taking the No. 48Y50 vein of Jiujiu-Daqou mining area as the research object, the geological mapping and rock geochemistry test analysis of the middle section of the mine are carried out. This paper summarizes the geological characteristics of the deposit and the rules of deep mineralization, and puts forward the prediction target area of the deep concealed orebody. On the basis of these works, the following understanding is obtained: 1, the trace map of the distribution of the rock decent distribution shows that, in the middle of the rock mass, The distribution of the surface is generally circular or elliptical. It is further proved that the magma of this kind of rock mass formed a "magmatic nuclear complex" uplift of .2during the process of upward invasion by regional compression shear stress, and established the discriminant mark of three-dimensional geometric structural characteristics of shearing similar lamellar granites, and analyzed the finite strain of the magma by finite strain analysis. By using Flynn diagram, the K value is 1.54, the magma is cooled and consolidated in the NW-SE extensional environment background, and the maximum principal stress orientation is close to horizontal .3.The homogenization temperature of the fluid inclusions in the hydrothermal alteration rocks after magmatic period, the salinity test results show that, The ore-forming fluid has the characteristics of moderate low temperature and low salinity, and the salinity is positively correlated with the temperature, and the pressure calculation results of inclusions show that the pressure of the place with stronger alteration is less than that of the weaker part of alteration. In the process of temperature decreasing gradually, the prediction index of deep ore-forming is established, the distance between the enrichment zone of deep gold deposit is about 200 m, and two ore-forming prediction models of deep vein are set up. The prediction depth of No. 50 vein ore body in deep prospecting area is approximately between 840m~1450m and that of No. 48 vein ore body in deep prospecting area is approximately between 1000m~1400m.
【学位授予单位】：中国地质大学(北京)
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P618.51

【相似文献】