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马钦忠 《地震学报(英文版)》2008,21(6):618-628
On July 4,2006,a MS5.1 earthquake occurred in Wen’an county of Hebei Province of which the epicenter is near the Beijing city.The six geoelectric field monitoring stations have been in operation for several years around the Beijing area to examine the relationship between electric field changes and earthquake.This paper firstly explains the principle of the eliminating noise method by using multi-dipole observation system of the geoelectric field.Then the data observed at the stations are studied and a lot of abnormal signals preceding the Wen’an earthquake are selected,of which five abnormal signals of the geoelectric field are finally recognized as the precursory signals.The result shows that 1 there probably exists the precursory signals of the geoelectric field preceding the Wen’an earthquake;2 there are sensitive sites in the spatial distribution of the abnormal variation of the geoelectric field before the quack;3 the anomalous signals do not appear synchronously,and their durations are not same at dif-ferent stations;4 the amplitudes of the abnormal signals recorded at Baodi station are small,but large at Changli station,while the latter is farther from the epicentral area than the former. 相似文献
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马钦忠 《地震学报(英文版)》2008,(6)
On July 4,2006,a MS5.1 earthquake occurred in Wen'an county of Hebei Province of which the epicenter is near the Beijing city.The six geoelectric field monitoring stations have been in operation for several years around the Beijing area to examine the relationship between electric field changes and earthquake.This paper firstly explains the principle of the eliminating noise method by using multi-dipole observation system of the geoelectric field.Then the data observed at the stations are studied and a lot ... 相似文献
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认识地震电信号特征对地震短临预报具有重要意义.通过陕甘宁晋地区、川滇地区、山东及其周边地区和上海地区的换流站接地极向地下注入2100—4600 A大电流,研究各地区地电场的变化特征,以深入地认识地电场信号的区域性变化实质.研究显示:① 在陕甘宁晋地区,高沙窝大电流源的附加地电场可被分布于鄂尔多斯地块边缘弧形地带的490 km范围内的10个台站观测到,而距该信号源以西150 km的台站均未观测到该信号;② 在川滇地区,丽江信号源的南部地区观测到的信号强度和距离远大于北部地区.对于西昌大电流源,只有距其10 km处的小庙台和540 km处的仙女山台可观测到信号,而其它十几个台站均未观测到;③ 在山东和上海地区,可被观测到的人工源信号的最远距离及其特征各不相同,亦与陕甘宁晋和川滇地区大为不同;④ 对于本文所研究的地区,信号的波形变化存在着随台站与信号源距离的增加畸变程度增大的现象,一些台站只能记录到大电流开始和结束时的尖峰脉冲信息.针对上述变化特征,本文从机理和地质条件等方面进行了一些有益的探讨,以期加深对地震电信号变化特征的认识. 相似文献
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<正>地震电磁学在地震预测研究领域占有重要位置.长期观测研究表明,在地震发生前会出现许多电磁异常现象.多年来,国内外学者利用这些异常信息开展了地震预测探索研究.自20世纪以来,地震电磁异常现象越来越引起人们的兴趣和重视,绝大多数强烈地震都有临震异常现象的发现与记载.到目前为止,国内外学者对地震前电磁异常现象与地震的关系进行了许多观测、实验和研究,积累了十分宝贵的经验和资料,为人们认识地震前电磁异常的现象提供了越来越丰富的震例. 相似文献
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马钦忠 《地震科学（英文版）》2008,21(6):618-628
On July 4, 2006, a MS5.1 earthquake occurred in Wen’an county of Hebei Province of which the epicenter is near the Beijing city. The six geoelectric field monitoring stations have been in operation for several years around the Beijing area to examine the relationship between electric field changes and earthquake. This paper firstly explains the principle of the eliminating noise method by using multi-dipole observation system of the geoelectric field. Then the data observed at the stations are studied and a lot of abnormal signals preceding the Wen’an earthquake are selected, of which five abnormal signals of the geoelectric field are finally recognized as the precursory signals. The result shows that ? there probably exists the precursory signals of the geoelectric field preceding the Wen’an earthquake; ? there are sensitive sites in the spatial distribution of the abnormal variation of the geoelectric field before the quack; ? the anomalous signals do not appear synchronously, and their durations are not same at different stations; ? the amplitudes of the abnormal signals recorded at Baodi station are small, but large at Changli station, while the latter is farther from the epicentral area than the former. 相似文献
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青藏高原北缘晚新生代的差异性隆起特征 总被引：8，自引：0，他引：8
在青藏高原的研究中,一个涉及高原隆升过程和机理的重要科学问题就是高原差异性隆升问题。文中初步研究了晚新生代以来青藏高原北缘的这种差异性隆升特征。研究表明,高原北缘山系隆升变化的差异性是很明显的。自23.7 Ma以来西昆仑山、阿尔金山和祁连山平均剥蚀率分别有4次阶梯式、谷—峰—谷—峰—谷式和二次阶梯式的变化形式。在3.6 Ma BP以前,青藏高原北缘山系的差异性隆升总体上呈现出东高西低的地貌特征;在3.6～1.7 Ma青藏运动发生期间,高原北缘山系的差异性隆升特征是西强东弱;在0.6 Ma以来,高原北缘山系的隆升差异性呈现出西强—中弱—东次强的特征。自1.7 Ma以来青藏高原北缘西昆仑山褶皱带平均缩短应变为38％,阿尔金山褶皱带平均缩短应变为8％,祁连山褶皱带平均缩短应变为15％。这和它们的高度在此期间的差异特征极为相似。 相似文献