共查询到20条相似文献，搜索用时 46 毫秒
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《地震地磁观测与研究》2016,(5)
根据攀枝花地震台川05井所处构造环境,研究其水位观测前兆异常,探讨对应地震的中长期、短临异常时空变化规律和形态变化幅度等动态特征,试图寻找川05井水位观测前兆异常变化与地震的对应关系,给出川05井水位短临异常变化幅度与震级、震中距的经验公式,初步获得水位异常变化与震中的关系,为今后水位异常预测地震发生地提供依据。 相似文献
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地下水位短临异常演化特征及其与地震关系的研究 总被引：3，自引：1，他引：3
本文对1976年唐山地震以来华北地区Ms≥5．0地震前的地下水位异常资料进行了系统整理，分析研究了水位短临前兆异常的时空演化特征及其与地震的关系。结果表明：震前水位短临异常的空间分布主要集中在一定范围并沿活动断裂带展布，且不均匀；大部分地震的水位短期异常较临震异常多；震前水位短期异常向临震异常过度时，分布区向震源区收缩，但在震中距100km左右以内这种现象不明显；震级与短临异常展布范围、短期异常幅度有一定关系，而与临震时期异常大小的关系不明显；地震发震时间与异常的超前、持续以及等待时间有关；地震发生地点与异常分布特征有关，震中往往不在短临异常集中区的几何中心，而是在异常范围内的某一侧或异常迁移方向附近。 相似文献
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归纳总结了安庆M_S4.8地震、高邮-宝应M_S4.9地震前出现的地下流体异常,并对其形成机理作了初步讨论。结果显示,这2次地震前地下流体异常特征比较相似。在时间进程上,都表现出中期趋势背景异常与短临异常的配套性特征。在空间分布上,中期趋势背景阶段,水位异常均表现为震中附近流体井水位呈趋势性转折上升,而震中外围流体井水位呈趋势性转折下降的特点。且转折上升的流体井在空间上的分布方位与地震的发震断层走向一致。在短临阶段,异常均表现为先向外迁移继而向震中靠拢的特点。水位在空间上的规律性分布可能受区域应力场作用以及区域构造格局所控制。 相似文献
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地壳形变短临异常与地下水位短临异常关系及识别方法的初步研究 总被引：2，自引：0，他引：2
对1976以来华北地区Ms≥5．0地震前的地壳形变和地下水位资料进行了系统整理，分析研究了地壳形变短临异常与地下水位短临异常间的关系，假如把相距不超过70km的一组形变与水位异常称为一个异常对次，则有：①临震异常对次远远小于短期异常对次；无论是短期异常还是临震异常，形变异常开始时间大部分早于水位异常开始时间；②住短期异常过程中，变形压或压缩与水位升、变形张或膨胀与水位升的异常对次所占比例不高；变形压或压缩与水位降、变形张或膨胀与水位降的异常对次所占比例较高，且变形张或膨胀与水位降占优，在临震异常过程中，变形压或压缩与水位升的异常对次所占比例远远大于变形张或膨胀与水位升的；③地壳形变短临异常与地下水位短临异常的关系可表示为Y=a0x＋a1，其中y和x分别为地下水位和地壳形变短临异常规测值。最后提出了判断短临前兆异常的新方法，即异常放大法。 相似文献
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利用井口水位对构造应力的响应，分析了地下水位在强(大)地震孕育过程中，中短期应力变化的响应，研究了地震前地下水位从中期异常过渡到短期异常的特征及演变过程。结果显示，当地下水位出现趋势上升、或趋势下降，动态变化规律异常为中期异常，这一时段通常为一年到三年；趋势上升、或趋势下降异常出现明显转折，则中期异常结束；中期异常出现转折后，其异常过程显示上下波动或拉平图像，这一时段为过渡性异常，属于中期异常向短临异常的过渡时段。当水位再次出现明显转折，则为短(临)期异常开始出现。而水位异常图像出现的趋势上升、或趋势下降、打破正常年动态变化规律形态，取决于井孔含水层系统在大震孕育过程的应力调整再积累阶段所处部位；尤其是取决于观测水点位于地质构造块体的构造带上，还是相邻块体的构造带上。水位震前异常的特征，源于地震孕育过程中应力异常区的形成。 相似文献
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１９９５年４月１５日营口高坎Ｍ＿Ｌ５．０地震，震中区烈度达Ⅵ度。总结发现，震前在一定的震兆异常背景上，出现一批短临前兆异常，如深井水位、水氡、水温、水汞、地倾斜、地电阻率、宏观等。分析认为，它可能是介质较薄弱的老震区对大区域应力场作用增强的反映，是我省震情发展中一次重要的地震事件。 相似文献
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《国际泥沙研究》2014,(4)
正Director:Shangfu Kuang,China Vice-directors:Chunhong Hu,China Duihu Ning,China Guangquan Liu,China The International Research and Training Center on Erosion and Sedimentation(IRTCES)was jointly set up by the Government of China and UNESCO on July 21,1984.It aims at the promotion of international exchange of knowledge and cooperation in the studies of erosion and 相似文献
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《中国科学:地球科学(英文版)》2014,(3)
正SCIENCE CHINA Earth Sciences,an academic journal cosponsored by the Chinese Academy of Sciences and the National Natural Science Foundation of China,and published by Science China Press and Springer,is committed to publishing high-quality,original results in both basic and applied research. 相似文献
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Richard D. Hey 《地球表面变化过程与地形》1979,4(1):59-72
Feedback mechanisms, which operate upstream through drawdown and backwater effects and downstream through sediment discharge are responsible for channel evolution. By combining these mechanisms with channel processes it euables a dynamic process-response model to be developed to simulate the initial evolution of straight gravel-bed channels. When erosion commences on a land surface, sediment entrained in the headwater reach by hydraulic action is selectively transported, deposited and reworked. This produces a damped oscillation between degradation and aggradation as the channel and valley respond to spatial and temporal variations in sediment calibre and hydraulic conditions. The initial cut and fill phases are responsible for valley incision and floodplain development while secondary and subsequent activity can produce river terraces. Eventually sediment entrainment in the headwaters declines as slopes are reduced. Subsequent channel evolution is relatively insignificant because it is dependent on local weathering activity producing material that can be transported on declining slopes. Therefore landforms produced during the initial phase of development, when local weathering was non-limiting, dominate the landscape. 相似文献
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Based on relocating the Jiujiang-Ruichang earthquake sequence which occurred on November 26, 2005 in Jiangxi Province with the double-difference （DD） algorithm and master event technique, the paper discusses the focal mechanism of the main shock （MsS.7） and the probable seismo-tectonics. The precise relocation results indicate that the average horizontal error is 0.31kin in a EW direction and 0.40kin in a NS direction, and the average depth error is 0.48kin. The focal depths vary from 8kin to 14kin, with the predominant distribution at 10kin - 12kin. The epicenter of the main shock is relocated to be 29.69^oN, 115.74^oE and the focal depth is about 10.Skin. Combining the predominant distribution of the earthquake sequence, the focal mechanism of the main shock and the tectonic conditions of N-E- and NW-strike faults growth in the seismic region, we infer that the main shock of the earthquake sequence was caused by a NW striking buried fault in the Rnichang basin. The nature of seismic faults needs to be further explored. 相似文献
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《中国科学:地球科学(英文版)》2014,(9)
正SCIENCE CHINA Earth Sciences,an academic journal cosponsored by the Chinese Academy of Sciences and the National Natural Science Foundation of China,and published by Science China Press and Springer,is committed to publishing high-quality,original results in 相似文献
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《中国科学:地球科学(英文版)》2014,(12)
正SCIENCE CHINA Earth Sciences,an academic journal cosponsored by the Chinese Academy of Sciences and the National Natural Science Foundation of China,and published by Science China Press and Springer,is committed to publishing high-quality,original results in both basic and applied research. 相似文献