莱州湾某海域控矿断裂带的磁法解释

发布时间：2018-05-09 12:46

本文选题：莱州湾 + 磁异常解释　；参考：《中国科学院大学(中国科学院海洋研究所)》2017年硕士论文

【摘要】：随着中国经济的快速发展,我国对黄金的需求量逐年增加,已连续多年位居世界之首。黄金需求量的提高增加了金矿勘探任务。胶东地区金矿资源丰富,且金矿床的分布与断裂构造密切相关。但近年来胶东地区浅、表部和陆地矿日益减少,勘探任务逐渐转向海域。高精度的磁测资料对于寻找断裂带的分布具有非常广的应用,本研究的目的是利用高精度磁力测量资料和地质资料推测莱州湾某海域的断裂带分布,预测金矿成矿靶区。研究区域的岩石建造主要为变质岩建造、砂岩建造、岩浆岩建造和砾岩建造几种类型,岩浆岩中的郭家岭型和玲珑型花岗岩与金矿的形成最为密切。整个胶东地区的构造特征类似棋盘的形状,基底褶皱构造主要为东西向,主要断裂构造线以北东-北北东向、东西向为主,还发育部分北西向的构造。三山岛断裂是与研究区域密切相关的断裂,实地勘查三山岛断裂从上到下依次为:胶东岩群岩层、未蚀变的玲珑花岗岩、弱至中等钾长石化或黄铁绢英岩化花岗岩带、断层泥带、中等至强烈黄铁绢英岩化花岗岩带、中等至强烈钾长石化花岗岩带、未蚀变的郭家岭花岗闪长岩。由磁异常等值线图、平面剖面图等图件,在研究区域划分出10个磁异常,对每个磁异常进行了单独的解释,利用经验切线法等方法得到各个磁异常地质体的异常中心、长轴短轴、埋深等数据。利用磁异常解析延拓、导数、化极的图件推测出研究区域北西向的F1断裂、F2断裂和F3断裂三条断裂带,同时基于ModelVision解释平台,进行二度半人机交互反演建模,根据高精度磁测数据反演推测出三个断裂的可能空间展布形态、赋存位置。经过对F1断裂带和F2断裂带的观察研究,根据磁异常的错动分布,追踪到一条北东向的断裂带,根据现有的地质资料推断,该断裂很有可能是三山岛断裂在研究区域的延伸。单一的利用高精度磁测资料对研究区域做解释推断具有多解性,如果增加其它地球物理、地质、化探的勘查资料,则能更好的解释和评价研究区域的构造展布以及研究金矿床的分布。在进一步勘查得到研究区域的其它资料后,本文所做的工作可作为进一步研究的基础。
[Abstract]:With the rapid development of China's economy, China's demand for gold has increased year by year and has been ranked first in the world for many years. The increasing demand for gold has increased the gold exploration task. There are abundant gold resources in Jiaodong area, and the distribution of gold deposits is closely related to fault structure. However, in recent years, the area of Jiaodong is shallow, the surface and land deposits are decreasing day by day, and the exploration task is gradually turning to the sea area. The high-precision magnetic data are widely used to find the distribution of the fault zone. The purpose of this study is to predict the distribution of the fault zone in a certain sea area of Laizhou Bay by using the high-precision magnetic measurement data and geological data, and to predict the ore-forming target area of gold deposits. The rock formations in the study area are mainly metamorphic formation, sandstone formation, magmatic formation and conglomerate formation. The Guojialing type and Linglong type granite in magmatic rock are most closely related to the formation of gold deposits. The tectonic characteristics of the whole Jiaodong area are similar to those of the chessboard, the basement fold structure is mainly east-west, the main fault line is NE NE, E W is dominant, and some NW trending structures are also developed. Sanshandao fault is a fault closely related to the study area. The sequence of field exploration of Sanshandao fault from top to bottom is as follows: rock formation of Jiaodong rock group, unaltered Linglong granite, weak to medium potassium feldspar or Huangtianshinite granite belt. Fault gouge zone, medium to strong Huangtaishinite granite belt, medium to strong potash feldspar granite belt, unaltered Guojialing granodiorite. From the isoline map and plane section map of the magnetic anomaly, 10 magnetic anomalies are divided in the study area, and each magnetic anomaly is explained separately. The anomalous center of each geomagnetic anomaly is obtained by means of the empirical tangent method. Long axis short axis, buried depth and other data. Three fault zones of F _ 1 fault F _ 2 fault and F _ 3 fault are inferred from the map of magnetic anomaly analytic continuation, derivative and polarization. Based on the ModelVision interpretation platform, the two-degree semi-human-computer interactive inversion modeling is carried out. Based on the high precision magnetic data, the possible spatial distribution and location of the three faults are inferred. Based on the observation and study of F1 and F2 fault zones, a NE fault zone was traced according to the dislocation distribution of magnetic anomalies. According to the existing geological data, the fault is probably an extension of Sanshandao fault in the study area. The single use of high-precision magnetic data to interpret and infer the study area has multiple solutions. If other geophysical, geological and geochemical exploration data are added, It can better explain and evaluate the tectonic distribution of the study area and the distribution of the gold deposits. The work done in this paper can be used as the basis of further research after further exploration and other data of the study area.
【学位授予单位】：中国科学院大学(中国科学院海洋研究所)
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P618.51;P631.2

【参考文献】