反射地震在胶东西北部变质岩区深部构造探测中的应用  

Application of reflection seismic for determing deep structural of metamorphic rock area in the northwest of Jiaodong

作　　者：王怀洪 朱裕振 孙超 王秀东 田思清 巩固 WANG HuaiHong;ZHU YuZhen;SUN Chao;WANG XiuDong;TIAN SiQing;GONG Gu(Shandong Provincial Research Institute of Coal Geology Planning and Exploration,Jinan 250104,China;Key Laboratory of Coal Geophysics,Chinese Geophysical Society,Jinan 250104,China;Shandong Provincial Academician Workstation,Jinan 250104,China;Engineering Technology Research Center on Coal Resources Informatization of Shandong Province,Jinan 250104,China)

机构地区：[1]山东省煤田地质规划勘察研究院,济南250104 [2]中国地球物理学会煤田地球物理重点实验室,济南250104 [3]山东省院士工作站,济南250104 [4]山东省煤炭资源数字化工程技术研究中心,济南250104

出　　处：《地球物理学进展》2021年第1期267-273,共7页Progress in Geophysics

基　　金：国家重点研发计划课题“辽东/胶东矿集区深部矿产勘查与增储示范”(2018YFC0603805);山东省煤田地质局科研专项基金(鲁煤地科字(2019)1号)联合资助。

摘　　要：焦家、三山岛、招平作为胶东西北部三大主要控矿断裂带,控制了胶西北地区近80%以上的金矿储量.金矿主要沿断裂倾角变化的平缓部位和陡、缓转折部位富集,构成了"阶梯式"分布型式.在复杂的区域地质构造背景下,如何清晰准确地预测控矿构造陡缓相间的倾角变化规律,成为金矿深部勘查必须要解决的问题.为了查明胶西北深部构造变化特征,本文应用地震方法进行了探索尝试.结合研究区以往地质、物探资料,构建了本区薄层反射地质模型,通过正演模拟研究,分析了采集参数,指导采集并获得了较高质量数据;针对变质岩区地震资料信噪比低、构造倾角大等特点,通过组合去噪、时频反褶积等技术手段,提高了地震信噪比;分析了该区地震反射波特征,以断面或蚀变带反射波直接进行断裂构造解释.明确了主要控矿构造在纵向上整体具有上陡下缓的"铲式"的特点,构造倾角30°~50°,局部达70°以上,呈倾角陡、缓相间阶梯式展布形态,且南东倾向断裂规模较北西倾向大.根据解释结果,预测了断裂带深度,指导了钻孔布设并获得了验证.Jiaojia, Sanshan island and Zhaoping are three major ore controlling fault zones in the northwest of Jiaodong, which control more than 80% of gold reserves in the northwest of Jiaodong. The regional geological structure background and ore controlling law are very complex. Gold deposits are mainly concentrated along the gentle part of the change of fault dip angle and the steep and gentle turning parts, forming a "stepped" distribution pattern. Under the complex regional geological structure background, how to clearly and accurately predict the dip angle change rule between steep and gentle ore-controlling structures has become a problem that must be solved in the deep exploration of gold deposits. In order to find out the characteristics of deep structure in the northwest of jiaodong.This paper has made an exploration attempt using seismic method. Based on the previous geological and geophysical data of the study area, a thin-layer reflection geological model of the study area is constructed. Through forward modeling research, acquisition parameters are analyzed to guide acquisition and obtain higher quality data. According to the characteristics of low signal-to-noise ratio and large structural dip angle of seismic data in metamorphic rock area, the seismic signal-to-noise ratio is improved by combining denoising, time-frequency deconvolution and other technical means. The characteristics of seismic reflection wave in this area are analyzed, and fault structure interpretation is directly carried out by reflection wave of section or altered zone. It is clear that the main ore-controlling structures have the characteristics of "shovel-like" with steep upward and gentle downward in the longitudinal direction. The structural dip angle is 30~50, and the local dip angle is more than 70. It is in the form of stepped distribution with steep dip angle and gentle alternation, and the fault scale in the southeast is larger than that in the north and west. According to the interpretation results, the depth of the fault zone

关 键 词：胶西北地区 反射地震 深部找矿 断面反射波 深部构造 

分 类 号：P631[天文地球—地质矿产勘探]