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1.
A. Ya. Sidorin 《Seismic Instruments》2010,46(4):377-382
A search for technogenic effects in the time series of earthquakes in Greece is carried out. The ine- quality of intra-week
distributions of earthquakes including the events of M ≥ 3.7 is shown. Sharp changes in the pattern of Rayleigh-Schuster’s
hodograph for the diurnal periodicity of earthquakes were revealed. They are located in the time vicinity of the moments of
the equinox. The result supports the idea of the natural gen- esis of the diurnal periodicity of earthquakes and the important
role of the Sun. 相似文献
2.
A. Ya. Sidorin 《Seismic Instruments》2010,46(4):351-355
A search for technogenic effects in the time series of earthquakes in Greece is carried out. The ine- quality of intra-week distributions of earthquakes including the events of M ≥ 3.7 is shown. Sharp changes in the pattern of Rayleigh-Schuster’s hodograph for the diurnal periodicity of earthquakes were revealed. They are located in the time vicinity of the moments of the equinox. The result supports the idea of the natural gen- esis of the diurnal periodicity of earthquakes and the important role of the Sun. 相似文献
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4.
I. B. Naguslaeva Yu. B. Bashkuev Yu. P. Malyshkov D. G. Buyanova 《Journal of Volcanology and Seismology》2008,2(3):184-188
This paper presents the results from long-term observations of parameters of the Earth’s natural impulsive electromagnetic field (ENIEMF) in the VLF range recorded in the Baikal Rift Zone. We consider the “seismic quiescence” effect and examine possible factors responsible for changes in the daily variations of the magnetic component before earthquakes. We demonstrate daily variations of the ENIEMF magnetic component and their correlation to local storm activity during a seismically quiet period. 相似文献
5.
Manana Kachakhidze Nino Kachakhidze-Murphy Giorgi Khazaradze Badri Khvitia 《地震科学（英文版）》2021,34(2):168-176
It is widely known that very low frequency/low frequency (VLF/LF) radiation has been recorded prior to large earthquakes in several seismically active countries of the world. The networks employed to detect this radiation consist of stationary transmitters and receivers. However, there are reported cases of existing networks being unable to detect any electromagnetic radiation prior to large earthquakes. In this study, we determined the optimal arrangement of a mobile VLF/LF electromagnetic radiation network to ensure the detection of an upcoming earthquake precursor. We consi-dered the possible arrangements of the VLF/LF mobile network based on certain physical considerations, and deve-loped a relatively simple arrangement that is completely different from the existing stationary networks. The suggested design will significantly increase the number of detected/predicted earthquakes by using the relevant electromagnetic radiation receivers strategically placed in regions of increased tectonic and seismic activity. 相似文献
6.
电磁辐射"EMOLS"仪观测结果原理及震例 总被引：10，自引：0，他引：10
“九五”期间研制的“EMAOS”电磁辐射仪,其接收原理是按大地电磁测深的原理改进而研制的。选择接收频段为0．01～10Hz,该频段探测深度在0～20km,是浅源地震发生的层位。记录的电磁扰动是在应力场作用下,动电效应产生的电磁场。电场和磁场同时记录增强了信息可信度的判断能力,记录震例表明,异常规律与已有模拟结果基本相同。因此,已总结的模拟记录预报指标等可在数字记录结果中使用。 相似文献
7.
The diurnal periodicity of seismic events of different energy from the Greece earthquake catalog was studied. Earthquake samplings of different energy with a known level of magnitude of completeness were compiled. Parameters of the diurnal periodicity of earthquakes in different time and magnitude intervals were analyzed. Significant diurnal periodicity of earthquakes with M ≤ 4.1 was revealed. The most important result of the paper is the discovery of the diurnal periodicity of the representative earthquakes with M = 3.2–4.1. The diurnal periodicity of representative earthquakes cannot be explained at the base of the prevailing hypothesis considering the diurnal periodicity of earthquakes as an apparent phenomenon resulting from diurnal changes in the real sensitivity of the seismic network due to diurnal variations of seismic noise. 相似文献
8.
The daily periodicity in four regions of the Dushanbe–Vakhsh area is analyzed. The study considers representative, nonrepresentative, and intermediate-energy earthquakes. Analysis of the specific features of the shape of the diurnal variation on workdays and weekends make it possible (1) to reliably conclude that the anomalous daily variation on workdays in medium-energy earthquake samplings is of technogenic origin and (2) suggest similarities in samplings of the weakest and strongest earthquakes. Apparently, the catalog includes a large number of industrial blasts. The number of blasts in earthquake samplings of various epochs and energies is estimated. 相似文献
9.
Space and ground-based experiments have shown evidence of natural short-period VLF emissions in which separate spectral elements are repeated with a periodicity of 2–7 s. Their basic morphological properties are found on the basis of original experimental data. In our opinion, excitation of such emissions is the result of quasi-linear relaxation effects that compensate for natural spectral dispersion. The quasi-linear relaxation of the energetic electron distribution function incrementally changes wave cyclotron instability and hence the VLF emission spectral forms. Some properties of the quasi-linear interaction of whistler waves with magnetospheric radiation belt electrons are studied. It is shown that quasi-linear relaxation can increase the cyclotron instability at the leading edge of an electromagnetic pulse. This effective saturation of absorption facilitates the division of VLF hiss-like emission into separate electromagnetic pulses without spectral modification from one pulse to the next. Some features and manifestations of this effective saturation of absorption are discussed. The results are important for a better understanding of temporal and spatial structures of VLF whistler-mode emissions and energetic electron fluxes. 相似文献
10.
A. Ya. Sidorin 《Seismic Instruments》2009,45(1):90-94
The diurnial periodicity of Garm Polygon earthquakes of various energy classes K [(magnitudes M): weak, K < 6.0 (M < 1.1); moderate, 6.0 < K < 8.0 (1.1 < M < 2.2); strong, K > 8.0 (M > 2.2)] has been studied. The time series of weak earthquakes is characterized by maximum activity at night and a clear diurnal periodicity that practically disappears for moderate earthquakes. Such periodicity can be traced again in the time series of the strong earthquakes practically antiphased to weak earthquakes; i.e., the maximum strong earthquakes occurred during the day time. 相似文献
11.
青海平安电磁辐射在中强震前短期前兆异常特征及预报效能研究 总被引：2，自引：0，他引：2
分析和整理了青海平安电磁辐射台自1993年7月以来的资料，发现震前平安单台电磁辐射在中强地震临震前有最大脉冲信号，并通过对无震异常，地震异常的分析判断，对其预报效能进行了R值评价。 相似文献
12.
《地震学报(英文版)》1996,9(3):447-454
In order to investigate the physical mechanism of seismo-electromagnetic signals, many scholars from China and other countries
have carried out laboratory and field experiments of rock samples by loading them up to fracture in recent ten-odd years.
In each of these experiments, the phenomenon of electromagnetic radiation was observed during the process of rock sample fracture.
However, the experimental results can not explain the non-synchronous electromagnetic radiation in actual observation records.
In these records, some stations displayed anomalies but some others did not, and the signals of different frequency bands
observed by the same station did not occur simultaneously. This has brought about many difficulties to the application of
electromagnetic radiation in earthquake prediction. The experimental result of this paper can explain the phenomenon of non-synchronous
electromagnetic radiation. In the experiment of this paper, rock samples are uniaxially compressed up to fracture. The antennas
of different frequency bands are installed two meters away from the rock sample in different directions. The electromagnetic
signals during the whole process of rock sample fracture are recorded synchronously by a 14-channel tape recorder. The experimental
results are as follows: (1) signals of the four frequency bands: VLF, MF, HF and VHF, are all recorded during the main fracturing
process of rock samples, but signals of different frequencies may somtimes occur non-synchronously; (2) the intensity of electromagnetic
radiation is the highest at the moment when the main fracture occurs, but signals in different directions are of different
intensities. The above results are consistent with the non-synchronous electromagnetic radiation observed in real earthquakes.
It seems possible to predict the orientation of future seismic source by the electromagnetic method of the LF or VLF frequency
bands.
Contribution No. 95A0075, Institute of Geophysics, SSB, China.
The paper is translated by Prof.Jie-Fan HUANG, Peking University from the Chinese into English version. 相似文献
13.
A. Ya. Sidorin 《Seismic Instruments》2014,50(3):246-267
The features of the diurnal periodicity of earthquakes with different energies in Japan are studied. The spatiotemporal parameters of different earthquake sets are investigated in detail using various techniques including analyses of amplitudes, dispersion, spectra and correlation. The phases of seismic flows are studied using the modified Rayleigh-Schuster method. Lomb-Scargle periodograms are used to study the frequency of variations in seismicity. The parameters of the sets of earthquakes having different energies obtained in this study indicate changes in phase of the diurnal periodicity of earthquakes to the opposite near the magnitude of completeness. The very clear midday effect is noted. 相似文献
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电磁辐射与孕震过程的初探 总被引：2，自引：1，他引：2
通过1994年青海共和的几次强余震和1999年河南县Ms5.1，玛沁Ms5.0，以及2000年甘肃景泰Ms5.9，兴海Ms6.6级地震前后平安电磁波资料的分析，总结了电磁辐射在进入短临阶段后的一些特征，得出了在孕震过程中电磁辐射异常与地震的关系，并初步探讨了地震电磁辐射源的形成与影响电磁辐射的可能因素。 相似文献
16.
A. Ya. Sidorin 《Seismic Instruments》2011,47(1):89-92
A 15-min periodicity of seismic events in the catalog of earthquakes in Greece is discovered. It is most vividly expressed
in the time series of weak and shallow events; however, it also occurs in the series of rather strong representative and deep
earthquakes. 相似文献
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18.
A. Ya. Sidorin 《Seismic Instruments》2010,46(3):237-249
The catalog of earthquakes that happened in Greece over the period of 1964 to 2008 was used for the analysis of their diurnal periodicity in this region. The quality of the catalog was examined with the defining of the representativeness levels of earthquakes in different selections. The earthquakes, including relatively strong events with the magnitude M ≥ 4.0, demonstrate diurnal periodicity with seasonal differences in their course reflected in their higher summer seismicity as compared with the winter one. 相似文献
19.
例举了杭州地震台投入超低频数字地震电磁辐射仪（EMAOS-L）以来的两组临震前电磁辐射观测异常资料现象,并对观测资料进行了分析和探讨。 相似文献
20.
通过省内、省外台站分布情况、台址情况、观测记录仪器使用情况,观测记录仪器的性能指标,如观测仪器探头类型、架（埋）设方式,记录仪器的采样率、分辨率,震例情况等从电磁辐射的发生机理出发进行深入细致的分析,找出地震前电磁辐射异常信息量、异常起始时间及持续时间与震中距、震级的关系。 相似文献