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1、前言自然电位Vsp作为地电台站的正式观测项目,一直与地电阻率同时观测。尽管各地电台都积累了大量的自然电位资料,但对这些资料作认真地分析研究却很少。这不仅由于自然电位的复杂多变,也与人工观测的时间间隔及数据处理不当有关。 相似文献
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河源地电台全空间地电阻率试验 总被引：5，自引：0，他引：5
河源地电台开展的深孔短极距试验观测，其电极深度达６５ｍ左右，μ值（Ｈ／Ｌ）达２．４。这种近似全空间的地电阻率观测方法，经试验证明在降低地电台站地表环境干扰因素的影响，提高观测精度，降低线路造价和维护费用等诸方面的效果是明显的． 相似文献
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随着全国越来越多的高压直流线路投入运行，地电场观测数据的质量受到严重干扰。本文从高压直流输电干扰对地电场观测的影响机理出发，以江苏地区为例，对其5年来高压直流输电线路对地电场观测数据的影响特征进行分析总结，得出相关结论：①当地电场观测数据受高压直流输电线路干扰时，地电场观测数据会出现畸变，持续一段时间后，不平衡电流消失，数据恢复正常；②地电场观测数据产生畸变的方向与观测台站的装置布设方式、接地极相对观测台站的位置有关；③高压直流输电线路接地极距离江苏地电台站较远，同一台站同一方向受同一高压直流输电线路影响的长短极距观测数据变化幅度之比接近1；④不同次高压直流输电干扰在同一台站出现地磁干扰变化幅度一致时，同一台站的地电场观测变化幅度不一定一致，与台站和接地极之间的地下电性结构的导电性变化有关。 相似文献
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通过对河北省4个地电场台站的观测资料全面分析判断,总结地电场干扰变化的可能因素;对"十五"新建的两个地电台站受到的干扰做出分析、判断;并结合台站实际观测环境,解决干扰源,对提高观测资料质量有一定的意义. 相似文献
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分析龙门石窟地下金属管道对地电观测的影响,通过对金属管道多种方法处理后,使之恢复地电原始观测环境,为地电台站遇到此类干扰提供参考. 相似文献
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地震台站地电场观测会受到各种因素的干扰,必须快速发现并消除干扰源,以保障观测数据的正常输出。2019年5月17日—6月4日,昌黎地震台地电场观测受不明原因干扰,观测数据产生畸变,与已知干扰类型数据特征进行对比分析,发现与常见干扰源所致数据变化形态特征不同;按照干扰数据变化特征,假设干扰源与观测台站的相对位置关系,布设简易的野外观测点,成功定位本次观测干扰源。最终确认,昌黎台地电场干扰由位于台站东南方向的铁件铸造厂变压器电缆漏电所致。此次干扰源排查,可为同类地电台站观测数据干扰分析提供参考。 相似文献
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以影响地电观测质量的主要因素及映震能力作为地电台站监测能力的主要评价指标,对安徽省5个地电台站的监测能力进行了综合评价,得到了安徽省地电前兆的基本情况,为安徽省未来的地电台站建设奠定了基础. 相似文献
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地电阻率观测各类干扰源的分析与研究 总被引：2，自引：1，他引：1
地电阻率观测是我国地震前兆监测的重要手段之一,目前已积累了大量的观测资料和强震震例。但随着农村经济的发展和城市现代化轨道交通设施的建设,使得部分地电台站观测环境发生较大变化,导致地电阻率前兆观测资料受到较强的干扰。本文通过对国内现有地电阻率观测资料的分析、干扰源的调研,研究了各类干扰产生的原因及识别方法。并根据已有的研究成果,对地电阻率观测抑制干扰的技术和方法及数据使用与处理提出了相应的建议。 相似文献
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Xuanhui Yang Yu Jeffrey Gu Ping Shen Xiqiang Liu Zhizhen Zheng 《Pure and Applied Geophysics》2006,163(8):1515-1536
Signal extraction from overlapping seismic records is a common problem in geophysical data analysis. Identification and separation
of multiple seismic arrivals, analysis of large earthquakes as multiple point sources, and calculation of the true yield of
a large nuclear explosion from interfering small explosion, all hinge on our ability to effectively decouple two interfering
wave signals. This paper presents a method for signal separation based on an adaptive filtering technique. We apply a semi-deconvolution
algorithm to overlapping explosion records and S/SKS phase groups, and then perform noise reduction and signal decoupling
under different a priori conditions and assess the stabilities using a variance reduction approach. We demonstrate, through numerical experiments
and analysis of seismic station records, that the adaptive method can be both robust and practical for regional and teleseismic
applications. 相似文献
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John Briscoe 《Ground water》1984,22(5):573-578
An exact expression is derived for the optimal spacing between interfering wells in a rectangular well field in an ideal confined aquifer. A simple, practical method for determining the optimal spacing is presented. The optimal spacing is shown to be substantially different from the spacing determined by use of the Theis formulation. The economic savings resulting from use of the revised approach are evaluated and found to be considerable, especially when the number of wells is large and the transmissivity of the aquifer low. 相似文献
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E. SZARANIEC 《Geophysical Prospecting》1977,25(2):302-307
The geophysical system of horizontal layers may be considered as a large scale system. A large class of systems is identified which are equivalent to the geophysical processes in horizontal layering. The property of hierarchical aggregation of layers forms a convenient framework within which the peculiarities of such systems can be studied. Geophysical processes in multilayered media may serve as a reference physical model for a specified class of large scale systems, in order to take advantage and to apply geophysical methods of data processing, system analysis, and parameter identification. Specified large scale systems are decomposable, like geophysical systems, by use of recursive schemes. A category particulary susceptible to such a decomposition is any polynomial which is stable inside the unit circle. Sophisticated geophysical concepts, such as anisotropy, equivalence, and disappearance, can be used to approximate or to simplify the system by vanishing or adjusting the decomposition coefficients. 相似文献
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It is well recognized that the time series of hydrologic variables, such as rainfall and streamflow are significantly influenced by various large‐scale atmospheric circulation patterns. The influence of El Niño‐southern oscillation (ENSO) on hydrologic variables, through hydroclimatic teleconnection, is recognized throughout the world. Indian summer monsoon rainfall (ISMR) has been proved to be significantly influenced by ENSO. Recently, it was established that the relationship between ISMR and ENSO is modulated by the influence of atmospheric circulation patterns over the Indian Ocean region. The influences of Indian Ocean dipole (IOD) mode and equatorial Indian Ocean oscillation (EQUINOO) on ISMR have been established in recent research. Thus, for the Indian subcontinent, hydrologic time series are significantly influenced by ENSO along with EQUINOO. Though the influence of these large‐scale atmospheric circulations on large‐scale rainfall patterns was investigated, their influence on basin‐scale stream‐flow is yet to be investigated. In this paper, information of ENSO from the tropical Pacific Ocean and EQUINOO from the tropical Indian Ocean is used in terms of their corresponding indices for stream‐flow forecasting of the Mahanadi River in the state of Orissa, India. To model the complex non‐linear relationship between basin‐scale stream‐flow and such large‐scale atmospheric circulation information, artificial neural network (ANN) methodology has been opted for the present study. Efficient optimization of ANN architecture is obtained by using an evolutionary optimizer based on a genetic algorithm. This study proves that use of such large‐scale atmospheric circulation information potentially improves the performance of monthly basin‐scale stream‐flow prediction which, in turn, helps in better management of water resources. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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本文给出了利用高频天波返回散射雷达对1987年9月23日日环食电离层效应的观测结果.分析表明,日食期间在日环食带电离层存在明显的不均匀结构和小尺度的波动,而日食过后在见食电离层区域出现大尺度的波动现象. 相似文献
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本文根据ＬＥＯ中等离子体温度低，密度高，德拜长度小的特点，采用薄鞘层近似，计算了离子收集电流；根据电流平衡方程，考虑表面二次电子发射，计算了大型航天器表面在沉降电子流辐照下的充电特性。 相似文献
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本文给出了利用高频天波返回散射雷达对1987年9月23日日环食电离层效应的观测结果.分析表明,日食期间在日环食带电离层存在明显的不均匀结构和小尺度的波动,而日食过后在见食电离层区域出现大尺度的波动现象. 相似文献
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Earthquake behavior of variable rupture-scale on active faults and application of the cascade-rupturing model 总被引：4，自引：0，他引：4
闻学泽 《地震学报(英文版)》2001,14(4):404-416
IntroductionThe earlier concept of the characteristic earthquakes means those earthquakes recurring along the same portion of active fault zones, and having nearly the same size, displacement and rupture scale (Schwartz, Coppersmith, 1984). However, more and more evidences have suggested that the rupture(s scale of earthquakes recurred on an individual fault portion has variability (Thatcher, 1990). For instance, the rupture of the 1906 San Francisco, California, earthquake with magnitude 8.… 相似文献