Large, moderate, small earthquakes and seismic fortification criterion     

沈建文  石树中 《地震学报(英文版)》2004,17(5):589-595

IntroductionAccordingtoEarthquakeResistanceandDisasterReductionLawforthePeoplesRepublicofChina,twomethodsareadoptedforseismicdesignoftheconstructionprojectsinChina.Forkeyprojectsandtheprojectseasytocauseserioussecondarydisasters,seismicsafetyevaluationsmustbecarriedout.Andbasedontheresults,seismicfortificationstandardsaredeterminedtomakeseismicdesign.Forgeneralindustrialandcivilbuildings,seismicdesignsarecarriedoutaccordingtotheseismicfortificationstandardsstipulatedbyseismiczonationmap(Ch…  相似文献   

地壳介质弹性和电性各向异性研究的新进展   总被引：3，自引：2，他引：3       下载免费PDF全文

李清河  阮爱国  范小平  金淑梅 《地震工程学报》2004,26(1):10-17

分析了地壳介质各向异性研究的现状，指出了弹性和电性各向异性研究中存在的问题，提出了联合利用弹性和电性各向异性研究地球介质特征及提取物性参数的正反演方法．理论研究和地震过程的实际资料表明，将弹性和电性结合起来研究地壳介质各向异性具有清晰明确的物理意义，是各向异性研究的一个非常有发展前景的新领域。  相似文献   

基于“双差法”地震精确定位研究2002年12月14日玉门5.9级地震的发震断层和发震机制   总被引：4，自引：5，他引：4       下载免费PDF全文

荣代潞  李亚荣 《地震工程学报》2004,26(3):223-227

利用双差地震定位方法对2002年12月14日玉门5．9级地震主震和余震序列进行了精确定位，在此基础上讨论了本次地震的发震断层和发震机制。  相似文献   

陕西中南部的视应力场研究   总被引：2，自引：1，他引：2       下载免费PDF全文

王卫东  张永志  邵广周  刘国华  邹志伟  狄秀玲 《地震工程学报》2004,26(4):343-346

利用西安数字地震台网的宽频带数字地震记录，计算了陕西中、南部地震的视应力水平，并讨论了泾阳5．2级地震前后地震视应力的时间变化特征及视应力与震级的关系。  相似文献   

流动地磁测量中地震异常信息的探索          下载免费PDF全文

刘义高  胡诚  张明  李立风  潘海涛 《地震工程学报》2004,26(4):353-356

S方法将同一测期一条流动地磁测线各测点的变化叠加，可抑制单个测点的干扰，使可能存在的震磁异常信息凸现。本研究了安徽省流动地磁测线S异常与邻近地区小震震群活动频次和中强地震的关系；探讨了“震情窗”地区S异常与“震情窗”相关地区中强地震的相关性；讨论了同一测期流动地磁测线各测点δf“同向变化”现象。  相似文献   

多尺度分解在地震信号处理中的应用   总被引：1，自引：0，他引：1  

陈飞  赵永  刘阳  周云好 《中国地震》2004,20(4):405-409

利用小波分析中的多尺度分解及信号消噪技术，对记录不清、信噪比小、震相无法辨认的地震信号进行处理。结果表明：多尺度分解在弱震信号提取和弱震相的识别等方面有很好的效果。  相似文献   

福建及台湾海峡地震预警工程架构探索   总被引：2，自引：0，他引：2  

王洪涛  陈箴 《福建地震》2004,(2)

福建及台湾海峡是海陆板块碰撞到板内地震活动过渡带 ,东侧毗邻台湾板缘地震带 ,西侧为福建内陆板内地震活动区。这是得天独厚的观测研究大陆边缘地震构造带强震活动及板块动力学的良好地域。当前 ,我国进入全面建设小康社会历史时期 ,为防御地震造成社会灾害 ,实现以人为本 ,防患于未然 ,势必需要建构一个实用化的地震预警工程及其机制。本文即是在对福建及台湾海峡近 30多年以来观测研究的基础上 ,提出应用现代空间技术、数字地震、计算机网络等技术架构地震预警工程与机制的一种设想。  相似文献   

川西北倒三角形断块东部区域强震带形成机制与地震活动特征     

蒋良文  王士天  李渝生  王运生 《地球科学进展》2004,(Z1)

川西北倒三角形断块东部区域地处青藏高原东部边缘地带,地跨川西北高原及其与四川盆地过渡带的高山峡谷区,属我国著名的南北向地震带的中段,因其特定的大地构造环境和强烈的现代地壳构造运动,导致其在强大的近东西向构造应力场的驱动和平卧“A”字型控震构造体系的控制下,沿两侧边界断裂向东强力楔入,于“构造急剧收口带”之西侧形成了一个近SN向地跨三大构造单元的强震带,强震沿该带有规律的往返迁移和重复发生,且地震活动强弱具有较明显的分形特征。  相似文献   

In-plane and anti-plane strong shaking of soil systems and structures     

G. Gudehus  R. O. Cudmani  A. B. Libreros-Bertini  M. M. Bühler 《Soil Dynamics and Earthquake Engineering》2004,24(4):319-342

The concept of in-plane and anti-plane shaking is introduced with a rigid block on a plane surface with Coulomb friction. Using a hypoplastic constitutive relation to model the mechanical behaviour of the soil, numerical solutions for a rigid block on a thin dry or saturated soil layer are obtained. The coupled nature of dynamic problems involving granular materials is shown, i.e. the motion of the block changes the soil state—skeleton stresses and density—which in turn affects the block motion. Motions of the block as well as soil response can be more realistically calculated by the new model. The same constitutive equation is applied to the numerical simulation of the propagation of plane waves in homogeneous and layered level soil deposits induced by a wave coming from below. Experiments with a novel laminar shake box as well as real seismic records from well-documented sites during strong earthquakes are used to verify the adequacy of the hypoplasticity-based numerical model for the prediction of soil response during strong earthquakes. The response of a homogeneous earth dam subjected to in-plane and anti-plane shaking is investigated numerically. In-plane and anti-plane shaking is shown to cause nearly the same spreading of a sand dam under drained conditions, whereas under undrained conditions anti-plane shaking causes stronger spreading of the dam. The dynamic behaviour of a breakwater founded on rockfill and soft clay during the 1995 Kobe earthquake is back-calculated to show the good performance of the proposed numerical model also with a structure. Section 9 deals with buildings on mattresses of densified cohesionless soils or fine-grained soils with granular columns, slopes with ‘hidden’ dams and structures on piles traversing clayey slopes to show the suitability of hypoplasticity-based models for the earthquake-resistant design and safety assessment of geotechnical systems.  相似文献   

Deep seismic reflection profiling in the Archaean northeastern Yilgarn Craton, Western Australia: implications for crustal architecture and mineral potential     

B.R. Goleby  R.S. Blewett  R.J. Korsch  D.C. Champion  K.F. Cassidy  L.E.A. Jones  P.B. Groenewald  P. Henson 《Tectonophysics》2004,388(1-4):119

Deep seismic reflection data across the Archaean Eastern Goldfields Province, northeastern Yilgarn Craton, Western Australia, have provided information on its crustal architecture and on several of its highly mineralised belts. The seismic reflection data allow interpretation of several prominent crustal scale features, including an eastward thickening of the crust, subdivision of the crust into three broad layers, the presence of a prominent east dip to the majority of the reflections and the interpretation of three east-dipping crustal-penetrating shear zones. These east-dipping shear zones are major structures that subdivide the region into four terranes. Major orogenic gold deposits in the Eastern Goldfields Province are spatially associated with these major structures. The Laverton Tectonic Zone, for example, is a highly mineralised corridor that contains several world-class gold deposits plus many smaller deposits. Other non crustal-penetrating structures within the area do not appear to be as well endowed metallogenically as the Laverton structure. The seismic reflection data have also imaged a series of low-angle shear zones within and beneath the granite–greenstone terranes. Where the low-angle shear zones intersect the major crustal-penetrating structures, a wedge shaped geometry is formed. This geometry forms a suitable fluid focusing wedge in which upward to subhorizontal moving fluids are focused and then distributed into the nearby complexly deformed greenstones.  相似文献