Progress in Earthquake Science and Technology in China: Review and Prospects (Ⅰ)     

Chen Zhangli 《中国地震研究》2001,15(4):329-345

In the article the author looks back the hard development course and great progress in earth quake science and technology in China during the last near a half of century and expounds the following 3 aspects: (1) The strong desire of the whole society to mitigate seismic disasters and reduce the effect of earthquakes on social-economic live is a great driving force to push forward the development of earthquake science and technology in China; (2) To better ensure people‘ s life and property, sustainable economic development, and social stability is an essential purpose to drive the development of earthquake science and technology in China; and (3) To insist on the dialectical connection of setup of technical system for seismic monitoring with the scientific research of earthquakes and to better handle the relation between crucial task, current scientif ic level, and the feasibility are the important principles to advance the earthquake science and technology in China. Some success and many setbacks in earthquake disaster mitigation consistently enrich our knowledge regarding the complexity of the conditions for earthquake occurrence and the process of earthquake preparation, promote the reconstruction and modernization of technical system for earthquake monitoring, and deepen the scientific research of earthquakes. During the last 5 years, the improvement and modernization of technical system for earthquake monitoring have clearly provided the technical support to study and practice of earthquake prediction and pre caution, give prominence to key problems and broaden the field of scientific research of earth quakes. These have enabled us to get some new recognition of the conditions for earthquake oc currence and process of earthquake preparation, characteristics of seismic disaster, and mecha nism for earthquake generation in China‘s continent. The progress we have made not only en courages us to enhance the effectiveness of earthquake disaster mitigation, but also provides a basis for accelerating further development of earthquake science and technology in China in the new century, especially in the 10th five-year plan. Based on the history reviewed, the author sets forth a general requirement for develop ment of earthquake science and technology in China and brings out 10 aspects to be stressed and strengthened at present and in the future. These are: upgrade and setup of the network of digitized seismic observation; upgrade and setup of the network for observation of seismic pre cursors; setup of the network for observation of strong motion; setup of the laboratories for ex periment on seismic regime; establishment of technical system for seismic information, emer gency command and urgent rescue; research on short-term and imminent earthquake predic tion; research on intermediate- and long-term earthquake prediction; research on attenuation of seismic ground motion, mechanism for seismic disaster, and control on seismic disaster; ba sic research fields related to seismology and geoscience. We expect that these efforts will signifi cantly elevate the level of earthquake science and technology in China to the advanced interna tional level, improve theories, techniques, and methods for earthquake precaution and predic tion, and enhance the effectiveness of earthquake disaster mitigation.  相似文献   

Age estimates of coastal terraces in the Andaman and Nicobar Islands and their tectonic implications     

Kusala Rajendran  C.P. Rajendran  Anil Earnest  G.V. Ravi Prasad  K. Dutta  D.K. Ray  R. Anu 《Tectonophysics》2008,455(1-4):53-60

The great Indian Ocean earthquake of December 26, 2004 caused significant vertical changes in its rupture zone. About 800 km of the rupture is along the Andaman and Nicobar Islands, which forms the outer arc ridge of the subduction zone. Coseismic deformation along the exposed land could be observed as uplift/subsidence. Here we analyze the morphological features along the coast of the Andaman and Nicobar Islands, in an effort to reconstruct the past tectonics, taking cues from the coseismic effects. We obtained radiocarbon dates from coastal terraces of the island belt and used them to compute uplift rates, which vary from 1.33 mm yr^− 1 in the Little Andaman to 2.80 mm yr^− 1 in South Andaman and 2.45 mm yr^− 1 in the North Andaman. Our radiocarbon dates converge on  600 yr and  1000 yr old coastal uplifts, which we attribute to the level changes due to two major previous subduction earthquakes in the region.  相似文献   

Nonlinear dynamic finite element simulation of Alibey earth dam     

Bilge Siyahi  Haydar Arslan 《Environmental Geology》2008,55(1):77-85

In this study, dynamic behavior and earthquake resistance of Alibey earth dam was investigated. The dam was modeled with four node plane-strain finite elements (FE) and displacement-pore pressure coupled FE analyses were performed. Nonlinear material models such as pressure dependent and independent multi yield materials were implemented during the analyses. Transient dynamic FE analyses were performed with Newmark method. The Newton-Raphson solution scheme was adopted to solve the equations. Liquefaction and/or cyclic mobility effects were considered during the analysis. For the FE analyses, OpenSees (Open System for Earthquake Engineering Simulation) framework was adopted.  相似文献   

Integration and magnitude homogenization of the Egyptian earthquake catalogue   总被引：2，自引：0，他引：2  

H. M. Hussein  K. M. Abou Elenean  I. A. Marzouk  A. Peresan  I. M. Korrat  E. Abu El-Nader  G. F. Panza  M. N. El-Gabry 《Natural Hazards》2008,47(3):525-546

The aim of the present work is to compile and update a catalogue of the instrumentally recorded earthquakes in Egypt, with uniform and homogeneous source parameters as required for the analysis of seismicity and seismic hazard assessment. This in turn requires a detailed analysis and comparison of the properties of different available sources, including the distribution of events with time, the magnitude completeness, and the scaling relations between different kinds of magnitude reported by different agencies. The observational data cover the time interval 1900–2004 and an area between 22°–33.5° N and 25°–36° E. The linear regressions between various magnitude types have been evaluated for different magnitude ranges. Using the best linear relationship determined for each available pair of magnitudes, as well as those identified between the magnitudes and the seismic moment, we convert the different magnitude types into moment magnitudes M _W, through a multi-step conversion process. Analysis of the catalogue completeness, based on the M _W thus estimated, allows us to identify two different time intervals with homogeneous properties. The first one (1900–1984) appears to be complete for M _W ≥ 4.5, while the second one (1985–2004) can be considered complete for magnitudes M _W ≥ 3.  相似文献   

台湾暖流起源的研究     

苏志清  钱清瑛 《中国海洋大学学报(自然科学版)》1988,(1)

根据台湾东北海域的水文资料分析,作者对台湾暖流起源提出以下看法:台湾暖流起源于黑潮分支和台湾暖水,黑潮分支为主要源泉。台湾暖流的深层水完全来自黑潮分支的深层水,不具有暖流性质,而其上层水是由黑潮分支的上层水和台湾暖水组成。由于台湾暖水有明显的季节变化,与此相应,台湾暖流也发生相应的变化。  相似文献   

Deformation Patterns of an Accretionary Wedge in the Transition Zone from Subduction to Collision Offshore Southwestern Taiwan   总被引：1，自引：0，他引：1  

Char-Shine Liu  Benoit Deffontaines  Chia-Yu Lu  Serge Lallemand 《Marine Geophysical Researches》2004,25(1-2):123-137

Swath bathymetry data and seismic reflection profiles have been used to investigate details of the deformation pattern in the area offshore southwestern Taiwan where the Luzon subduction complex encroaches on the passive Chinese continental margin. Distinctive fold-and-thrust structures of the convergent zone and horst-and-graben structures of the passive margin are separated by a deformation front that extends NNW-ward from the eastern edge of the Manila Trench to the foot of the continental slope. This deformation front gradually turns into a NNE–SSW trending direction across the continental slope and the Kaoping Shelf, and connects to the frontal thrusts of the mountain belt on land Taiwan. However, the complex Penghu submarine canyon system blurs the exact location of the deformation front and nature of many morphotectonic features offshore SW Taiwan. We suggest that the deformation front offshore SW Taiwan does not appear as a simple structural line, but is characterized by a series of N–S trending folds and thrusts that terminate sequentially in an en-echelon pattern across the passive Chinese continental slope. A number of NE–SW trending lineaments cut across the fold-and-thrust structures of the frontal accretionary wedge and exhibit prominent dextral displacement indicative of the lateral expulsion of SW Taiwan. One of the prominent lineaments, named the Yung-An lineament, forms the southeastern boundary of the upper part of the Penghu submarine canyon, and has conspicuous influence over the drainage pattern of the canyon  相似文献   

台湾海峡纽形动物初报   总被引：1，自引：1，他引：1  

孙世春 《海洋科学》1995,19(5):45-48

首次报道台湾海峡产的纽形动物，包括沙栖原细首纽虫、浮游拟脑纽虫、椒状岩田纽虫、中华平裂纽虫和马顿氏潘丁纽虫，共５种。除椒状岩田纽虫在琉球群岛有报道外，均为东海新记录。  相似文献   

台湾海峡西部柱状沉积物粘土矿物的分析   总被引：4，自引：0，他引：4  

游仲华  唐锦龙 《台湾海峡》1993,12(1):1-7

根据台湾海峡西部10个柱102个样品的X 射线衍射等分析,鉴定了该区粘土矿物组合与含量变化,分析了其与沉积环境的关系.结果表明,该区粘土矿物组合大多数站位以伊利石含量占首位,绿泥石和高岭石次之,且含少量蒙脱石;伊利石含量随距岸、水深的增加而递增,高岭石则反之;蒙脱石含量与火山活动密切相关,绿泥石含量呈斑块状分布;775和819号站有典型的陆相层,为早玉木冰期的“台湾陆桥”或“东山陆桥”提供有力证据.  相似文献   

台湾海峡中北部上升流区各种形态磷的化学特性   总被引：4，自引：0，他引：4       下载免费PDF全文

陈水土 《海洋与湖沼》1993,24(6):664-670

根据１９８８年７月调查资料讨论了台湾海峡中北部海域夏季上升流区各种形态磷的分布特征。结果表明，上升流中心区（即海坛岛东侧一带水域）具有低温、高盐、低溶解氧；ＤＩｐ，ＴＤＰ，ＰＰ，ＴＰ较高；ＤＯＰ较低（０．２７）；及ＤＩＰ／ＤＯＰ比值（约为１）较高的特性。ＤＯＰ是该海域磷的主要形态（占ＴＰ的４９．２％），其含量分布及其形态转化与生物活动直接相关，是该海域生物生产力高的体现。  相似文献   

1990年12月14日台湾强震的预报判据     

顾延芬 《台湾海峡》1993,12(1):81-84

本文运用福建省沿海气象要素的异常变化,作台湾省的中、短期地震预报,取得了成功的效果。采用长乐历年各月14时最低气压的距平值,作台湾省未来4～7个月内出现强震的预报依据,并采用热异常进行短临跟踪。当秋冬季节连续4d 长乐、福州、台北的气温均比广州累计高出10℃时,预报未来1～5d 台湾省出现7级强震。又根据近百年来台湾发生的强震,统计其活动季节,得到近20年来7级地震发生的时间,绝大部分在9～12月。  相似文献