首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 84 毫秒
1.
台湾海峡滨海断裂带的构造特征与活动性   总被引:11,自引:1,他引:10  
根据台湾海峡滨海断裂带活动断裂调查得到的海底地形、重力、地磁和多道地震探测资料,对滨海断裂带的构造特征与活动性进行了研究。该断裂带总体呈NE向分布,东北端起自牛山岛以东海域,西南端止于兄弟屿以东海域,大体沿50~60m等深线展布,全长约500km,是华南大陆与台湾海峡海盆的分界断裂;断层面近于直立,切穿地壳;在主压应力轴为NWWSEE方向的应力场作用下,断裂以右旋走滑为主,兼逆冲性质;断裂带两侧地形反差大,最新活动性强,控制着两侧新生代地层的沉积,;断裂带上地震活动频繁,是福建沿海地震活动最活跃的断裂带。  相似文献   

2.
长乐-诏安断裂带是福建沿海的主要活动断裂之一,沿断裂带曾发生多次破坏性地震,是福建省陆域上的主要发震构造。中国东部地区破坏性地震的发生与晚更新世活动断裂有密切联系,因此研究长乐-诏安断裂带在晚更新世的活动具有重要意义。在对福建省东山县最新发现的长乐-诏安断裂东支东山段剖面的野外详细调查的基础上,通过对断层下盘地层和断层上断点以上地层中钾长石光释光测年,确定了长乐-诏安断裂带东支东山段的具体活动时间在(34.8±8.3)~(48.0±3.5)ka之间,显示该断裂至晚更新世晚期仍有活动,属晚更新世活动断裂;通过震级(M)与地震断层位错量(D)经验关系拟合法估算,该断裂的最大发震能力为6.5~7.0级地震。该晚更新世活动断裂的确定和最大震级估算,为长乐-诏安断裂带的活动性提供了确切年代学证据,为东山县地区城市安全评价提供了依据。  相似文献   

3.
研究了福建沿海自晚更新世以来控制主要断陷盆地、平原和海湾的断裂活动性状,认为这些构造在所讨论的时段内具有强烈的张性活动,而发生于区内的地震与这些构造的近期张性活动有关。  相似文献   

4.
为厘定太原盆地中部潜在的发震断层情况,对田庄断裂实施了浅层地震勘探,结果表明:1)田庄断裂可分为3个区段,各区段内均发育北、南支断裂,其中北支断裂为主断裂;2)除断裂西端及中-东段转折部位断面呈近似“N”形结构外,其余断面均呈“Y”形;3)西段断裂带宽度最小,东段断裂带宽度最大。利用年代学测试方法结合钻孔剖面确定断裂的活动年代及滑动速率,断裂中段的活动年代为晚更新世晚期,上断点最小埋深为39.3 m,晚更新世以来最大断距为2.9 m,最大滑动速率为0.0415 mm/a;断裂西段及东段的活动年代为中更新世,中-东段转折部位上断点最小埋深为37.4 m,晚更新世以来最大断距为2.7 m,最大滑动速率为0.0461 mm/a。基于浅层地震揭示的基岩破裂长度,采用地震矩方法对田庄断裂进行地震危险性概率分析,确定断裂的最大潜在震级及发震概率。  相似文献   

5.
太行山南端浅层速度结构成像和隐伏断裂探测   总被引:1,自引:0,他引:1  
利用太行山南端的深地震反射剖面数据,运用初至波层析成像方法反演得到该区域的浅层P波速度结构和基底面展布形态,发现剖面浅部的P波速度变化与沉积盖层厚度和断裂分布有着较好的对应关系。利用跨断裂完成的浅层地震反射剖面,对区域内2条第四纪隐伏活动断裂进行高分辨率成像。结果表明,汤西断裂为东倾的正断层,控制汤阴地堑的西边界,活动年代为中更新世;汤东断裂为西倾的正断层,是汤阴地堑的主控边界断裂,活动年代为晚更新世。  相似文献   

6.
联合福建省近几年的GPS基本网、基准站观测数据和重力复测数据,反演福建块体的分块运动参数和主要活动断裂运动状态。结果显示,受欧亚板块、菲律宾海板块和太平洋板块相互碰撞的影响,福建地区块体的运动样式大体呈现顺时针方向的运动,造成北东向断裂作左旋走滑运动,而北西向断裂以右旋走滑为主。其中,长乐-诏安断裂带、邵武-河源断裂带和永安-晋江断裂带是块体内最活跃的断裂带,其左旋走滑速率分别为0.7±1.3、0.7±1.7和0.6±1.8mm/a,九龙江下游断裂带具有0.5±1.7mm/a的右旋走滑速率。  相似文献   

7.
为研究聊城-兰考断裂中段的第四纪活动特征,采用浅层地震勘探和钻孔联合剖面相结合的探测方法,跨断裂布设5条浅层地震勘探测线和1条钻孔联合地质剖面。钻孔联合地质剖面揭示聊城-兰考断裂中段上断点埋深为61.4~64.5 m,结合地层年代学结果判定,聊城-兰考断裂中段为晚更新世早期活动断裂。  相似文献   

8.
对福建省地震局成立以来采用常规地面测量手段监测构造形变的结果进行了回顾与总结,对两期GPS观测资料进行了分析,结果表明福建沿海的地震活动和构造形变皆受到区域应力场的控制,构造形变的总体特征为南强北弱、东强西弱,尤其是闽东南地区为地壳形变较集中的地区,同时也是地震活动较强的地区。在此基础上讨论了太平洋板块、菲律宾海板块、欧亚板块相互作用以及福建沿海北东向和北西向断裂对福建沿海构造形变的作用。  相似文献   

9.
鄂豫皖毗邻区属中强地震区,主要构造为东大别断块。其边界断裂(郯城—庐江断裂带和麻城—团风断裂带等)控制了块内英山—霍山北东向对角线多闭锁点右旋剪切破裂带的强震活动,它是研究区的主要强震构造带。根据地壳形变测量,东大别断块相对东西两大断块均呈右旋,这与中国东部晚新生代地壳扭动的方式一致。然而郯城—庐江断裂带中南段里剪压性,麻城—团风断裂为剪张性。其构造力学性质的差异,很可能是由于前者为二级断块的边界构造;而后者是该二级断块内的三级断块的边界断裂。此二级断块内的深部上地幔隆起导致了麻城—团风断裂带的剪切扩张运动。1913年以来麻城、商城地区的强震活动或许与此有关;而霍山地区的较强地震活动,则与英山、罗田上地幔凹陷北缘莫氏面急剧变化有联系。此外,1917年霍山 6~(1/4)级地震和1932年麻城6级地震的孕震构造系统的分析表明:断块内次级闭锁断裂发震和受主干断裂控制的次级断裂发震,是我国板块内部现代强震的一种普遍构造模型。  相似文献   

10.
利用9个GPS站水平和垂直向形变数据反演2022年台湾MW6.9地震破裂滑动分布。结果表明,此次地震破裂至地表,滑移以走滑为主兼逆冲分量,主要沿NNE向延伸,有2个破裂集中区,共释放地震矩约5.73×1019 Nm。基于GPS观测和位错理论模型对此次地震的地表形变进行分析,认为同震形变整体上符合台湾岛东海岸区域构造运动特征,菲律宾海板块俯冲欧亚板块是中央山脉断裂活动的主要动力来源。  相似文献   

11.
12.
The ability of cell to modulate the fluidity of plasma membrane was crucial to the survival of microorganism at low temperature. Plasma membrane proteins, fatty acids and carotenoids profiles of Antarctic psychrophilc yeast Rhodotorula sp. NJ298 were investigated at -3 ℃, 0 ℃ and 8 ℃. The results showed that plasma membrane protein content was greater at -3 ℃ than that at 8 ℃, and a unique membrane polypeptide composition with an apparent molecular mass of 94.7 kDa was newly synthesized with SDS-PAGE analysis; GC analysis showed that the main changes of fatty acids were the percentage of unsaturated fatty acids (C18∶ 1 and C18∶ 2) and shorter chain saturated fatty acid (C10∶ 0) increased along with the decrease of the culture temperature from 8 ℃ to -3 ℃; HPLC analysis indicated that astaxanthin was the major functional carotenoids of the plasma membrane, percentage of which increased from 54.6±1.5% at 8 ℃ to 81.9±2.1% at -3 ℃. However the fluidity of plasma membrane which was determined by measuring fluorescence anisotropy was similar at -3 ℃, 0 ℃ and 8 ℃. Hence these changes in plasma membrane's characteristics were involved in the cellular cold-adaptation by which NJ298 could maintain normal plasma membrane fluidity at near-freezing temperature.  相似文献   

13.
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 comprehensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose  相似文献   

14.
<正>Copyright Submfnion of a roanusatpt inks:that the work described has not been published before(exoept In the form of an abstrW or as part of a published lecture,review,or thesis);that it is not under consideration for publication elsewhere that its publication has been approved by ail  相似文献   

15.
<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 results on oceanography and marine fisheries.The fieldcovered include the physical,chemical,biological,geo-  相似文献   

16.
<正>The 35th IAHR World Congress was held in Chengdu,China from September 8 to September 132013.The title of the conference was:"The Wise Finds Pleasure in Water:Meandering through Water Science and Engineering".During the congress,1239 papers were presented in 139sessions for oral presentations and 7 sessions for poster presentations.After the Congress,a Committee was appointed to select some of the best papers presented at the Congress for publication,after a  相似文献   

17.
As an important component of the cryosphere,sea ice is very sensitive to the climate change.The study of the sea ice physics needs accurate sea ice thickness.This paper presents an electromagnetic-induction(EM) technique which can be used to measure the sea ice thickness distribution efficiently,and the successful application in Bothnian Bay.Based on the electromagnetic field theory and the electrical properties of sea ice and seawater,EM technique can detect the distance between the instrument and the ice/water interface accurately,than the sea ice thickness is obtained.Contrastive analysis of the apparent conductivity data obtained by EM and the value of drill-hole at same positions allows a construction of a transformable formula of the apparent conductivity to sea ice thickness.The verification of the sea ice thickness calculated by this formula indicates that EM technique is able to get reliable sea ice thickness with average relative error of only 12%.The statistic of all ice thickness profiles shows that the level ice distribution in Bothnian Bay was 0.4-0.6 m.  相似文献   

18.
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   

19.
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   

20.
Foreword     
正Rapid changes of Arctic sea ice cover have been in the focus of the international climate research community in recent years.Quite a few of nations have completed a large number of related surveys and research projects in the Arctic Ocean.Up to now,China has performed six research cruises to the Arctic Ocean resulting in a significant volume of research output.Improved knowledge on the atmospheree-sea ice-ocean interactions in the Arctic is a  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号