共查询到20条相似文献，搜索用时 78 毫秒
1.
2.
3.
4.
新丰江水库是世界上诱发Ms≥6.0级地震的四大水库之一,由于对水库大坝及时采取抗震加固措施,使其经受住1962年3月19日6.1级强震的考验,收到明显的经济效益和社会效益,成为我国抗震设防工作的一次成功实例,得到国内外专家的赞誉。在长达30余年中,新丰江水库区逐步建立了包括测震、地应力、地形变、地电、水化学等观测项目的水库地震监测网,对新丰江水库地震的发展趋势进行监测预报,取得连续的极其丰富的资料。新丰江水库的监测、研究在国际同学科领域中处于领先地位。所取得的成果为安定新丰江下游地区的人心,稳定社会秩序,为政府部门对水库蓄水和发电站正常运行等方面的决策提供了重要依据。 相似文献
5.
6.
7.
2008年5月12日14时28分汶川发生8级地震,造成通讯中断,为了及时了解紫坪铺水库大坝受损情况,发震后不到半小时就出发,距发生8级地震后不到3小时到达水库大坝,用相机记录下大坝受损情况,向大坝上的相关领导和业主汇报8级地震情况及其与紫坪铺水库大坝的位置关系,当天返回省地震局后立即向相关领导和部门汇报。2008年2月14日21时36分都江堰市发生3．3级地震,2月15日组织去现场工作,现场调查认为,地震中心点董家山隧道口的烈度为Ⅳ度;发震构造为龙门山前山断裂。 相似文献
8.
南水水库截流蓄水后,发生在库区的地震活动,属于水库诱发地震;其序列特征为小的震群型;未来诱发地震将小于Ms3.7级,不会影响大坝的安全。 相似文献
9.
10.
水库诱发地震与孔隙压力扩散系数研究——以紫坪铺水库为例 总被引：1，自引：0，他引：1
《国际地震动态》2015,(8)
<正>自从1945年第一次提出Mead湖水库诱发地震的事实以来,全球报道蓄水引起地震的水库超过150座。水库诱发地震问题一直受到广泛的关注。中国有100m以上的高坝114座,其中32座蓄水后地震活动显著增强。为了解决电力供应问题,中国的水库由少震的东部扩展到地震活动强烈的西部地区。2008年汶川地震的发生,使得紫坪铺水库在汶川地震中的作用问题受到关注。由此,对强震活跃地区水库的作用和机理的研究被提上日程,研究具有现实意义。 相似文献
11.
12.
汶川8．0级特大地震汉源县震害特点与烈度异常成因探讨 总被引：1，自引：0，他引：1
本文在汉源县地震灾害调查的基础上,通过收集前人在该区已取得的成果资料,采用综合分析、类比等方法,对汉源县地震烈度异常区震害及造成异常的原因进行了分析探讨。汉源县建筑物破坏形式以水平地震作用造成的“X”型剪切破坏为主,竖向地震造成的破坏较少。地震波传播路径、场地土层条件和地形地貌条件三者的耦合是造成汉源县烈度异常的主要原因,其中场地土层中占优势厚度的砾石层是造成场地地震波放大的主要内因。本文取得的初步结论为更加深入地科学研究本区地震烈度异常的原因提供了新思路。 相似文献
13.
汶川地震后的几点思考 总被引：1，自引：1，他引：0
本文认真思考了汶川地震对防震减灾各环节的影响,主要观点有:(1)地震预报很难,但不能不搞。(2)搞好建筑物的抗震设防、避让活断层与山地灾害隐患,或适当治理山地灾害隐患是震前防御减灾的有效途径。(3)汶川地震的紧急救援绩效卓著,但还有提升潜力。 相似文献
14.
Abstract The 2008 Wenchuan earthquake, a major intraplate earthquake with Mw 7.9, occurred on the slowly deforming Longmenshan fault. To better understand the causes of this devastating earthquake, we need knowledge of the regional stress field and the underlying geodynamic processes. Here, we determine focal mechanism solutions （FMSs） of the 2008 Wenchuan earthquake sequence （WES） using both P-wave first-motion polarity data and SH/P amplitude ratio （AR） data. As P-wave polarities are more reliable information, they are given priority over SH/ PAR, the latter of which are used only when the former has loose constraint on the FMSs. We collect data from three categories： （1） permanent stations deployed by the China Earthquake Administration （CEA）; （2） the Western Sichuan Passive Seismic Array （WSPSA） deployed by Institute of Geology, CEA; （3） global stations from Incorporated Research Institutions for Seismology. Finally, 129 events with magnitude over Ms 4.0 in the 2008 WES are identified to have well-constrained FMSs. Among them, 83 are well constrained by P-wave polarities only as shown by Cai et al. （Earthq Sci 24（1）：115-125,2011）, and the rest of which are newly constrained by incorporating SH/P AR. Based on the spatial distribution and FMSs of the WES, we draw following conclusions： （1） the principle compressional directions of most FMSs of the WES are subhorizontal, generally in agreement with the conclusion given by Cai et al. （2011） but with a few modifications that the compressional directions are WNW-ESE around Wenchuan and ENE-WSW around Qingchuan, respectively. The subhorizontal compressional direction along the Longmenshan fault from SW to NE seems to have a leftlateral rotation, which agrees well with regional stress field inverted by former researchers （e.g., Xu et al., Acta Seismol Sin 30（5）, 1987; Acta Geophys Sin 32（6）, 1989; Cui et al., Seismol Geol 27（2）：234-242, 2005）; （2） the FMSs of the events not only reflected the regional stress state of the Longmenshan region, but also were obviously controlled by the faults to some extent, which was pointed out by Cai et al. （2011） and Yi et al. （Chin J Geophys 55（4）：1213-1227, 2012）; （3） while the 2008 Wenchuan earthquake and some of its strong aftershocks released most of the elastic energy accumulated on the Longmen- shan fault, some other aftershocks seem to occur just for releasing the elastic energy promptly created by the 2008 Wenchuan earthquake and some of its strong aftershocks. （4） Our results further suggest that the Longmenshan fault from Wenchuan to Beichuan was nearly fully destroyed by the 2008 Wenchuan earthquake and accordingly propose that there is less probability for great earthquakes in the middle part of the Longmenshan fault in the near future, although there might be a barrier to the southwest of Wenchuan and it is needed to pay some attention on it in the near future. 相似文献
15.
Based on faults surveying and research data in the Tianjin offshore areas, through studying tectonic structure, Quaternary activity, deep structure, stress and strain fields and seismicity in the Tianjin offshore areas, the activity and tectonic features of the faults are determined synthetically. Using seismo-geological data, and the historical and modern seismicity data, the frequency-magnitude relationship model normalized by 500a is established and based on the relationship between the upper limit of maximum magnitude Mu and at/b, the maximum magnitudes of the sea section of the Haihe river fault and the Haiyi fault are calculated. Then Poisson probability model is adopted and the quantitative parameters, such as the maximum magnitude, occurrence probability, recurrence cycle of the faults in the south Tianjin offshore areas in the coming 50 - 200a, are calculated. 相似文献
16.
Using a time series method that combines both the persistent scatterer and small baseline approaches, we analyzed 9 scenes Envisat ASAR data over the L＇Aquila earthquake, and obtained a Shocke＇s displacement field and its evolution processes. The results show that： （1） Envisat ASAR clearly detected the whole processes of displacement field of the L＇Aquila earthquake, and distinct variations at different stages of the displacement field. （2） Preseismic creep displacement → displacement mutation when faulting → constantly slowed down after the earthquake. （3） The area of the strongest deformation and ground rupture was a low-lying oval depression region to the southeast. Surface faulting within a zone of about 22 km× 14 km, with an orientation of 135°, occurred along the NW-striking and SW-dipping Paganica-S. Demetrio normal fault. （4） In analyzing an area of about 54 km x 59 km, bounded by north-south axis to the epicenter, the displacement field has significant characteristics of a watershed： westward of the epicenter shows uplift with maximum of 130 mm in line-of-sight （LOS）, and east of the epicenter was a region with 220 mm of maximum subsidence in the LOS, concentrating on the rupture zone, the majority of which formed in the course of faulting and subsequence. 相似文献
17.
The non-tidal variation gained from continuous gravity observations in stations usually reflects the regional continuous gravity changes. In this paper we focus on studying the non-tidal variation of Baijiatuan station, Beijing where there are two different gravimeters （namely, L＆R-804 and PET-031）. Based on the original raw tidal records of two gravimeters from 2008 to 2011, we first remove various interference from raw data by the standard procedure software-Tsoft; then we model the solid earth tides, ocean tidal loading and pole tide through related parameters; after that we adopt a new segmented polynomial fitting method based on Tsoft to fit the complex drift of spring gravimeter; and finally we calculate the atmospheric loading effects by a linear regression model. After a series of processing we gain the non-tidal variation of the two gravimeters at Baijiatuan site, Beijing. Furthermore, to analyze the non-tidal variation preliminarily, we study the main component of related tidal data by power spectral density. Comparing the non-tidal variation of two different gravimeters, we find seasonal fluctuations in non-tidal results, which are in accordance with the water storage change. Therefore, we take into account the relevance of gravity changes and water storage based on the gravity data of GRACE and water data of the CMAP model from 2003 to 2011 at different sites in the Chinese mainland （Beijing, Chengdu, Shenyang and Shiquanhe） , and make a preliminary analysis on the relationship between gravity changes and water storage. 相似文献
18.
民国期间的《嘉陵江日报》对1933年发生在四川省茂县叠溪的地震进行过系列报道,其中根据地质学家常隆庆先生的信函对于该地震考察情况的报道尤为详尽。过去,这些资料从未被地震历史资料的文献收录,鲜为地震工作者所知,具有较高的史料价值。整理转载这6000余字的资料,并作了注释和说明,相信能够为今后的地震史料研究提供参考。 相似文献
19.
Monitoring of subsurface fluid （underground fluid） is an important part of efforts for earthquake prediction in China. The nationwide network, which monitors groundwater level, water temperature, and radon and mercury in groundwater, has been constructed in the last decades. Large amounts of abnormal fluid changes before and after major earthquakes have been recorded, providing precious data for research in earthquake sciences. Many studies have been done in earthquake fluid hydrogeology in order to probe the nature of the earthquake. Much progress in earthquake fluid hydrogeology has been made in the last decades. The paper provides a review of the advances in research on earthquake fluid hydrogeology over the last 40 years in China. It deals with the following five aspects： （1） an introduction to the development history of monitoring networks construction; （2） cases of different subsurface fluid changes recorded before some major earthquakes which occurred in the last decades; （3） characteristics of subsurface fluid changes following major earthquakes; （4） mechanism of subsurface fluid changes before and following earthquakes; （5） application of earthquake fluids in the hydrogeology field. 相似文献
20.
The indirect boundary element method （IBEM） is used to study three-dimensional scattering of obliquely incident plane SH waves by an alluvial valley embedded in a layered half-space. The free-field response of the layered half-space is calculated by the direct stiffness method, and dynamic Green＇s functions of moving distributed loads acting on inclined lines in a layered half-space are calculated to simulate the scattering wave field. The presented method yields very accurate results since the three-dimensional dynamic stiffness matrix is exact and the moving distributed loads can act directly on the valley boundary without singularity. Numerical results and analyses are performed for amplification of obliquely incident plane SH waves around an alluvial valley in a uniform half-space and in single layer over half-space. The results show that the three-dimensional responses are distinctly different from the two-dimensional responses, and the displacement amplitudes around alluvial valleys in a uniform haft-space are obviously different from those in a layered half-space. 相似文献