综合地球物理方法在山前隐伏断裂探测中的应用——以巍山—长山南坡断裂为例          下载免费PDF全文

赵建明  李明  费书民  张志相  高嘉琳 《地震工程学报》2021,43(5):1095-1102

针对探测山前隐伏断裂复杂困难的特点,以巍山—长山南坡断裂为例,采用浅层地震勘探和高密度电法勘探等地球物理方法并结合钻孔联合地质剖面资料,对巍山—长山南坡断裂的隐伏段的准确位置和活动性进行研究,确定断层的准确位置和产状等。研究结果表明,巍山—长山南坡断裂在唐山市区的隐伏段为S倾的正断层,倾角约78°,断距约3 m,上断点埋深约19 m;该断裂在市区的隐伏段为中更新世断裂,晚更新世以来不活动。  相似文献   

REGIONAL CHARACTERISTICS OF ENVIRONMENTAL CAPACITY FOR HEAVY METALS IN SIEROZEM ZONE AND ITS RELATION TO PHYSICALGEOGRAPHIC PROCESSES     

Xu Jialin  Yang Jurong  Xu hongning 《地理学报(英文版)》1994,(Z1)

l.IntroductionEllvironnle11talpo1lution,populationgroWtl1alldtheincreaseofresourcccoulllptiollarel1lattersofgreatconcerntopeopleal1overtl1eworld.ll1tl1ecourseofpreventillgandcolltrollil1gcnvirol1111entalpollutio1l,tl1cstud}:a11dutilizatio1iofenvironmelltaIcapacityhasattractedthescientists'attentioll.II1previousyears,thccontro1ofPOllutionwascarriedoutonlybylimitingtheconcentratiol1ofpollutantsil1wastesdischarged.However,inrecentyearsthesignifical1ceoftotalqual1titycontrolofpollutantdiscl1arge…  相似文献   

Comparative studies of Danxia landforms in China     

QI Deli  YU Rong  ZHANG Renshun  GE Yunjian  LI Jialin 《地理学报》2005,15(3):337-345

Danxia geomorphology originates from China. This paper studies the spatial distribution and differences in characteristics of Danxia landforms. Based on relevant research and investigations, three congregated areas of Danxia landform in China are discussed in this paper. They are the southeast area (including Jiangxi, Fujian, Zhejiang, Hunan and Guangxi provinces), the southwest area (the transitional zone of Yunnan-Guizhou Plateau and Sichuan Basin) and the northwest area (including Longshan mountain and along the banks of the Huanghe River and its anabranches). Not only the conditions of geology and geography of the three areas but also the differences of Danxia landforms of the three areas are analyzed. The Danxia landscape, characterized by upright-shaped peaks, Danxia mesa, stone wall, cave and vertical cave, "Danxia natural bridge", "a narrow strip of sky" and so on, often presents in the southeast area. The landscape of southwest area is characterized by Danxia escarpment faces and waterfalls. In the northwest area, the Danxia landscape has the traits of arid areas simultaneously, for example, mud-coating type, columniation type, board type, moreover, it is greatly different between these environmental factors such as the microclimate, water, wind, and the loess cover. Finally it explores the causes which lead differences in landform and also explains the landform formation process and its mechanism with reference to the rates of crustal uplift, the tectonic red-basin, and the external processes including working of running water, weathering, biogenic, gravity in each area of Danxia Landforms in China.  相似文献   

图像增强技术在重磁图像中的应用   总被引：2，自引：0，他引：2  

张丽莉郝天珧  吴健生王家林 《应用地球物理》2005,2(3):145-152

本文综述了图像增强技术在位场数据中的应用现状，并介绍了两种改进的图像增强技术，用于增强重磁图像特征。一种方法借鉴了直方图平滑化的思想，应用于位场彩色影像的色谱的自动确定。该方法的应用能够使色彩合理地配置，从而保证了图像的视觉效果和分辨率。另一种方法基于改进的Radon变化和梯度计算，用于重磁图像中线性特征的检测和增强。该方法能在变化域中突出显示线性特征，从而有利于线性特征的检测和增强。通过对简单图像和实际资料的应用，表明了两种方法在增强特征中的有效性。  相似文献   

中国东南沿海中生代酸性火山岩的锶和钕同位素特征与岩浆成因   总被引：26，自引：1，他引：26  

薛怀民  陶奎元 《地质学报》1996,70(1):35-47

中国东南沿海中生代火山岩叠置在几个不同的基底构造单元之上，不同单元内的火山岩在锶、钕同位素组成上存在着很大的差异。其中隶属于下扬子亚板块的浙西－赣东北区火山岩的＾８７Ｓｒ／＾８６Ｓｒ初始值普遍较低，而＾１４３Ｎｄ／＾１４４Ｎｄ初始值则较高。  相似文献   

Sr and Nd Isotopic Characteristics and Magma Genesis of Mesozoic Volcanic Rocks Along the Coastal Region of Southeastern China   总被引：6，自引：0，他引：6  

Xue Huaimin  Tao Kuiyuan  Shen Jialin 《《地质学报》英文版》1996,70(3):260-273

The Mesozoic volcanic rocks in the coastal region of southeastern China were superimposed on some different basement tectonic elements. The volcanic rocks developed in these different basement tectonic elements have great differences in Sr and Nd isotopic compositions. The rocks in western Zhejiang and northeastern Jiangxi Provinces which belong to the Lower Yangtze subplate have lower initial 87Sr/ 86Sr ratios, but are higher in initial Nd isotopic ratios. The initial 143Nd / 144Nd values of the volcanic rocks developed in the Cathaysian subplate increase clearly from early to late in time, and from the core of the Wuyishan uplift coastwards constantly, but the initial 87Sr/86Sr values tend to decrease. The isotopic characteristics and their spatial variations in Mesozoic volcanic rocks in the study region are, to a great extent, manifestations of the isotopic characteristics in basement metamorphic complexes, and the generation of the Mesozoic acid magma in this region is attributed to the recycling o  相似文献   

西昆仑库地伟晶辉长岩和玄武岩锆石SHRIMP年龄：库地蛇绿岩的解体   总被引：13，自引：0，他引：13  

张传林  于海锋  沈家林  董永观  叶海敏  郭坤一 《地质论评》2004,50(6):639-643

西昆仑“库地蛇绿岩“是中国西部地区研究程度较高的蛇绿岩之一。对这条蛇绿岩带的时代、构造背景至今存在很大分歧。笔者等在库地超镁铁岩体中 ,获得侵入于橄榄岩中的伟晶辉长岩锆石 SHRIMP年龄为5 2 5± 2 .9Ma,在库地一些克沟获得块状玄武岩锆石 SHRIMP年龄为 4 2 8± 19Ma,这表明库地超镁铁岩和库地一些克沟玄武岩不属于同一时代 ,因此它们可能形成的构造背景也存在差异 ,库地蛇绿岩应解体。本文提供的年代资料为研究这一地区的早古生代构造演化提供了新的资料  相似文献   

软土地区基坑围护结构设计的实践     

吴美玉  许家林 《上海国土资源》2003,(4):34-36

上海属软土地区，工程地质条件较差，由于城市建设用地的控制和周围建筑、道路、地下管线等环境的影响，作为地下工程基坑开挖的临时性围护结构的设计研究成为非常重要的课题：必须确保基坑自身的安全和对周边建筑、道路、地下管网保护，同时也必须做到经济合理、施工方便。作者通过具体工程设计实践浅谈基坑工程围护结构设计的几点心得。  相似文献   

2001年新疆-青海交界8.1级特大地震的特殊性、发震背景及对未来地震形势估计   总被引：2，自引：0，他引：2  

孙加林 《国际地震动态》2002,(9):11-13

2001年11月14日新疆－青海8．1级特大地震，是1951年当雄8．0级特大地震后，整整50年大陆上首发8级特大地震，它的发生虽然没有造成较大经济损失和人员伤亡，但它的科学意义和学术价值超过过去几十年来任何一次强震，它打破了我们对地震活跃期的划分和许多传统认识，同时对如何判断未来地震大形势提出了重大课题。  相似文献   

三维电阻率概率成像法研究   总被引：1，自引：0，他引：1  

刘小军  王家林  杨光亮  吴健生 《大地测量与地球动力学》2006,26(3):93-96

电阻率概率成像法是利用地表电场的测量值与电场扫描函数进行归一化的相似程度作为概率的成像方法。根据概率论的基本理论,引入幂函数并推导了电阻率异常发生概率函数。通过数值模型实验对此方法进行了验证,对多个孤立异常体和凹陷模型进行了概率成像。通过对浙江某地实测资料概率成像结果与常规最小二乘法反演结果进行比较表明,三维电阻率概率成像法能较好地分辨地下地电结构。  相似文献