【作者】 郭涛；

【导师】 翟裕生； 吕古贤；

【作者基本信息】 中国地质大学（北京） ， 矿物学、岩石学、矿床学， 2005， 博士

【摘要】 本文在区域地质和矿床地质研究的基础上,以胶西北金成矿带为例,以构造-流体-矿化分析为主线,试图用系统分析的方法探讨区域矿化特征和区域成矿规律。认为胶西北地区所发育的金矿床是同一成矿系统的综合产物。成矿物质中金主要来源于胶东群老地层和部分上地幔,硫同位素组成对其赋矿主岩或矿源岩具有继承性,成矿流体以岩浆水、岩浆水与大气降水的混合水为主。系统阐述了区域成矿系统的基本要素,认为中生代时胶东岩石圈的大规模减薄作用、区域动力体制转换和构造-岩浆活化作用是区域矿化集中分布的基本成矿条件。系统论述了区域成矿系统的蚀变矿化网络结构。认为蚀变矿化分布和发育情况明显受控于断裂裂隙构造的性质及容矿空间的差异,蚀变矿化具有明显的以水平为主的分带性;以构造-流体填图的方式,对蚀变矿化网络进行了研究,把以往着重于室内研究的蚀变矿化变成野外可以操作的工作手段和方法;在区域流体分析的基础上,认为本区金矿床成矿流体演化过程中出现三个温度峰值阶段,成矿温度在空间上自西向东有逐渐降低的趋势;成矿压力介于60～20Mpa 这个区间范围内。深入研究了成矿构造。借助有限单元法恢复解析成矿期的三维构造应力场,提出构造空间的差异及流体运移方式改变导致不同的蚀变矿化,对成矿作用过程中矿化裂隙的成生机制、成矿流体运移的方向、通道和驱动力等作了初步的分析;提出构造物理化学参量的空间分布反映了构造作用下流体运移时物理化学条件的分布与变化。认为深部构造控制了胶西北成矿带的空间展布,断裂构造系统控制着矿床的产出、矿体特征及矿床类型特征。综合研究了区域构造-流体-成矿作用,绘制了胶西北区域蚀变矿化网络图,提出了矿床产出的丛聚性、似等距性、对称性和矿体的侧伏及水平分带。提出区域成矿的地质界面、构造界面和构造物理化学参量界面;认为区域动力体制转换,构造应力场临界转换、构造岩带脆韧性转换和成矿构造物理化学参量的临界转换等共同组成一个多级、多因的临界转换系统,是矿化得以成生、发展和保存的先决条件。更多还原

【Abstract】 Study on the regional geology and deposit characteristics; take Jiaoxibei gold metallogenic belt as example, this paper try to discuss the regional mineralized characteristics and metallogenic law by method of systematic analysis. 1. Base on a systematic summary of former researcher’s accomplishments, the author thinks that all deposits in Jiaoxibei area were compositive results of the same regional metallogenic system. The gold element and sulfur isotope is mainly come from the Jiao dong group and points out that the metallogenic fluid includes magma fluid and mixed fluid. 2. The author expatiates the basic metallogenic element and put forward that the large scale lithosphere thinning, critical transition of regional dynamical system and tectonic-magma activation is the elementary metallogenic condition of concentrated mineralization. 3. Base on fundamental geological characteristics of regional metallogenic system, we emphatically engage in the metallogenic network by tectonic-liquid mapping and change the former indoor research to some means and method which can be used in field work. The author points out that the differential mineralization and alteration is mainly resulted from various fissures and there is an obvious horizontal zoning. 4. A detailed study on temperature, pressure and components of fluid inclusions in Jiaoxibei area, it means that there are three temperature period during the fluid evolution and the metallogenic temperature trends to decrease from west to east. The metallogenic pressure is mainly between 60～20Mpa. 5. By means of Finite Element, the author has resumed the three-dimensional stress field of metallogenic period. From study on the characteristics of mineralized fissures and channel, mode, genesis reason of liquid migrating under tectonics, in this paper, the author not only point out that differential genesis reason and migrating form lead to various mineralized characteristics but also bring forward that the spatial distribution of tectonophysicochemical parameters embodied the distribution and change of physicochemical conditions during fluid migration. 6. The deep structure determines the spatial distribution of Jiaoxibei ore belt. The fault system not only controls the deposits forming, ore bodies’ characteristics and deposit types, bust also control the centrality, equidistance, symmetry and horizontal zoning of deposit or ore bodies. 7. Base on above-mentioned research, the author still synthetically analyzed the tectono-fluid-minerzation and has finished the alteration-mineralization network map of Jiaoxibei area. The author has put forward to the geological interface, tectonic interface and tectonophysicochemical interface of regional metallogenic system and thinks that the critical transition and superposition of these interface is the precondition of ore-formation, evolution and conserve.更多还原