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1.
在野外地质调查基础上,对江南断裂带宣城敬亭山剖面上采集的3件断层泥样品中的石英颗粒进行透射扫描电镜(SEM)微形貌观察与统计。结果显示,江南断裂带为活动断裂,在新近纪和第四纪时期具明显的活动性,活动始于中新世,晚更新世达到高峰,活动方式以蠕滑为主;至全新世,断裂以粘滑方式持续活动;沿断裂带的地震记录表明,至近现代断裂仍处于活动状态。这些结论对于正确评价江南断裂带在第四纪的活动规律及该区自然灾害预防等具有重要意义。  相似文献   

2.
阐述了黄陵地块内部北西向雾渡河断裂的几何学分段、运动方式和剩余形变特征,指出晚更新世以来雾渡河断裂可能较为稳定。在暂不考虑全断层同时滑破的前提下,分段计算各段潜在地震强度为5.0≤M≤6.0。  相似文献   

3.
骊山北缘山前断层是渭河盆地东部一条具重要地震地质意义的活断层,第四纪以来活动标志明显。断层一带的断错地貌显示,该断层以引张倾滑兼反扭活动为特征;断层泥中石英碎屑的SEM形貌特征显示,断层粘滑活动标志显著;断面擦痕电算结果显示,断裂带引张构造应力场格局为:σ~1—NE64°∠12°,σ_2—NE20°∠74°,σ_3—SE154°∠2°;冲沟裂点的实测分析结果显示,全新世以来该断层可能有过七次以上的快速活动;陡坎扩散方程计算和热释光测年确定出了该断层距今12万年左右的一次强烈活动的年代。  相似文献   

4.
在仙女山-九畹溪断裂带野外地质调查的基础上采集12件断层泥样品,并对样品进行石英碎砾提取和扫描电镜微形貌观察。结果表明,仙女山断裂为一条以粘滑为主的活动断裂,最近一次较大规模的运动发生在中-晚更新世;九畹溪断裂带具有多期活动迹象,早期活动强于晚期,近期强烈活动在上新世至中更新世,为一条以粘滑运动为主的活动断裂。仙女山-九畹溪断裂带所构成的V型断裂组合表现为以仙女山断裂带为主导的构造格局。  相似文献   

5.
通过野外地质调查,结合地球物理探测手段,研究两郧断裂郧县盆地段地质与地球物理特征;参照两郧断裂带多个位置采集断层物质的SEM、TL测试成果,并结合本次对断层上断点沉积物OSL测年数据,对两郧断裂该段第四纪活动性进行分析。研究结果表明,两郧断裂在郧县盆地段埋深相对较深;断裂特征主要为逆断层,部分分支断裂显示为正断性质;断裂带最新活动时代为中更新世晚期-晚更新世早期。  相似文献   

6.
本文利用经过拟稳和伪逆平差等方法处理过的大地测量资料,分析了鲜水河断裂带的现今构造形变。表明该断裂带在近东西向区域压应力作用下,呈压性反扭,为典型的蠕滑—粘滑型断裂带。 断裂带蠕动段以水平反扭为主,前兆显示“V字型”异常形态,震后呈对数衰减。在虾拉沱,水平蠕动年速率为7.17±0.03毫米,倾向蠕动年速率为1.04±0.03毫米,两者之比为7:1。在粘结阶段,断裂带闭锁段无明显活动;而快速错动阶段,震中区发生大量级的水平反扭错动(达米级)及其伴随的松驰下沉(达分米级)运动。 现今构造形变和历史大震表明:道孚以北为蠕动段,以南为闭锁段。据此,鲜水河断裂带来来如果发生大震,则危险区可能在南段。  相似文献   

7.
根据对调查资料、航卫片判译和已有文献的综合分析,研究了西秦岭北缘断裂(XQLF)东段和海原断裂(HYF)南段的走滑转换、变形及其与陇山地块的相互作用。XQLF以几何学结构复杂和多期活动为特征,主带各段呈左阶斜列。HYF南段的陇县-宝鸡断裂(LBF)由4条断层组成70km的宽带,中更新世以来表现为左旋走滑运动。XQLF和LBF在运动过程中均产生走滑挤压或走滑拉伸的转换变形。被上述断裂切割围限的陇山地块,从晚白垩世至早第四纪一直处于强烈的挤压变形状态。中晚第四纪以来,可能还具有顺时针旋转变形和位移。  相似文献   

8.
在塔里木盆地顺北地区奥陶系走滑断裂带寻找碳酸盐岩"断溶体"型油气藏成为近年来油气勘探的热点。多口钻井显示顺北1号主走滑断裂带"断溶体"裂缝发育部位普遍具有异常高的自然伽马测井值。因此,可以根据异常高泥质含量参数来反映裂缝发育程度,进而指示含泥"断溶体"储层的发育位置。首先利用GeoEast软件提取了顺北1号走滑断裂带T74界面(一间房组顶)相干体属性并进行了断裂解释。根据5口井一间房组自然伽马测井数据,探讨了台地碳酸盐岩走滑断裂带断核和损伤带异常高泥质含量值与主干断裂带距离和裂缝发育程度之间的关系。结果表明:顺北地区奥陶系一间房组台地碳酸盐岩沉积环境稳定,背景泥质含量较低;NE向主走滑断裂带核部和裂缝发育部位的泥质含量远高于台地碳酸盐岩背景值,具有随着离主干断裂带距离增大和裂缝发育程度下降而降低的变化趋势,最终接近其背景值。由此表明,可利用自然伽马测井计算泥质含量,间接指示走滑断裂带"断溶体"储层发育程度。该研究为深层-超深层走滑断裂带储层评价提供了一种新的思路。   相似文献   

9.
为从现今庞大的GNSS观测网络中快速检测断层蠕滑形变,精细反演蠕滑时空分布及演变特征,提出集GNSS网络滤波、地表形变信息提取和地下断层蠕滑时空分布反演三者于一体的方法。该方法同时采用整个GNSS网络的时空观测阵列,利用断层形变高空间相关的特点,对覆盖断裂带地表的GNSS位移时空序列进行主成分分析,利用主成分信息快速检测并反演蠕滑断层的时空分布与演变过程。以2005年苏门答腊MW8.6地震震后余滑和2006年墨西哥Guerrero州慢滑移为例,本文方法可成功检测并反演蠕滑断层的时空分布及演变特征,结果与相关研究成果吻合。  相似文献   

10.
基于三维向错理论模拟倾角为60°的矩形断层在转动角不同量级和形式下引起的地表形变,分析断层转动对地表形变大小及空间分布的影响。利用向-位错模型,采用数值方法模拟鲜水河断裂带断层滑动与转动引起的地表形变,并与扣除趋势项的2009~2015年的GPS实测结果进行对比。研究表明:1)转动角大小与断层向错引起的地表位移场大小呈正比关系,位移场方向不变,转动方向不同时,地表位移场方向随之改变,大小不变,且断层附近地表位移场影响较大;2)基于向-位错组合模型对鲜水河断裂带模拟结果与GPS结果在大小和方向上均具有较好的一致性;3)鲜水河断裂带表现出一定的旋转特性,存在明显的分段差异性,具有一定的转换构造样式。  相似文献   

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12.
Based on the hydrographic data in austral summer during the 22nd Antarctic Expedition of China(2005/2006),some features can be found about the northern margin of Emery ice shelf as follows.The heat content in the surface layer(0-50 m) at the eastern end and the western end of the ice-shelf margin is much higher than that at the middle.The upper mixing-layer depth and the seasonal thermocline depth at the middle of the ice-shelf northern margin are much shallower than those at the both ends.However there is much less difference between the middle and the ends in the bottom layer.The remote sensing photos show that the inhomogeneity in the surface-layer water is closely related to the spatial distribution of the floes and polynia in the area.  相似文献   

13.
Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter.  相似文献   

14.
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprchensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose is to publish achievements in fundamental research,applied  相似文献   

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16.
《山地科学学报》2014,(4):I0004-I0009
<正>AIMS AND SCOPE(Editorial Policy)The Journal of Mountain Science(JMS)is devoted to mountains and their surrounding lowlands-ecoregions of particular global importance,with a particular emphasis on the important highlands/mountains in the world,such as the Tibetan Plateau,the Himalayas,the Alps,the Andes,the Rockies and many other mountain ranges of our planet.  相似文献   

17.
<正>The Journal of Mountain Science(JMS),founded in2004,is an international English-language journal on mountain sciences.JMS is supervised by the Chinese Academy of Sciences(CAS),sponsored by the Chengdu Institute of Mountain Hazards and Environment,CAS,published by Science Press China,and distributed by Springer exclusively throughout the world(excluding Mainland China).The JMS is published bimonthly,fulltexted in SpringerLink and CNKI,indexed/abstracted by  相似文献   

18.
Using the NCEP/NCAR reanalysis monthly 500 hPa height data on a 2.5 latitude-longitude grid and 1°×1° sea ice data,the polar vortex area,intensity index and arctic sea ice area index are calculated respectively,and the meridional distribution,period variation and the abrupts in the long range trend are analyzed to study their relationship.The results show that the meridional distribution of sea ice and polar vortex h-ave distinctive difference,the relative positions of them are different in the eastern and western hemispheres,and exept they have periods of 4 months,quasi half year,quasi year,4-5 years and 10 years commonly,and each of them has its own respective variation as well.The sea ice area is decreasing apparently since 1980's,so is the polar vortex area,but their abrupt changge time are different totally.The area of sea ice and polar vortex has prominent positive correlation,but the relationship of sea ice intensity,polar vortex intensity,polar vortex area is complicated.  相似文献   

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<正>The Journal of Ocean University of China(Oceanic and Coastal Sea Research)is a comprehensive academic quarterly sponsored by the Ocean University of China,published one volume per year.This journal is devoted to the publication of the theoretical and applied research  相似文献   

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