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221.
本文对福建泉州地磁台白水营老址与丰州镇董埔村候选新台址,使用高灵敏度,快速记录的磁通门磁力仪,对台址周围观测环境进行了全面对比监测,从地磁短周期脉冲干扰,地磁场变化形态,日变幅、时均值相关分析等方面进行评估,指出老址的周围环境干扰量已超出0.1nT的<<地磁台站观测规范>>要求,新址符合<<地磁台站观测规范>>要求,适宜建立永久性地磁基本台。 相似文献
222.
本文应用“地磁观测数据处理和方法研究程序”,分析了1989年-1993年发生在四川省内Ms≥4.7地震的震磁效应,结果证明该程序包实用性强,可用于该地区的日常监视预报工作。 相似文献
223.
G. S. Lakhina 《Surveys in Geophysics》1994,15(6):703-754
Electromagnetic fields and currents connect various regions of the earth's near space environment extending upto the magnetopause. Realization of this fact has lead to the concept of Global Electric Circuit (GEC) to describe the electromagnetic environment of the earth's atmosphere. Solar wind - magnetosphere - ionosphere coupling forms a vital component of GEC. Magnetospheric substorms represent a global interaction between the solar wind, the magetosphere, and the ionosphere. This article gives an overview of the solar wind - magnetosphere- ionosphere coupling processes with emphasis on the nonlinear particle dynamics in the magnetotail. Those aspects of the substorm processes which involve the chaotic dynamics are highlighted. Various methods based on nonlinear particle dynamics, linear prediction filtering techniques, phase space reconstruction techniques, and dynamical anologue models of geomagnetic activity are reviewed. It is shown that the solar wind- magnetosphere - ionosphere system behaves as a strongly coupled nonlinear dynamical system which could be driven from regular to chaotic behavior with low dimensionality when the solar wind forcing is strong enough. 相似文献
224.
陈伯舫 《地震学报(英文版)》1994,7(3):457-464
InvestigationsoftheseismomagneticeffectinthegeomagneticdiurnalvariationsPo-FangCHEN(陈伯舫)(DepartmentofPhysicsandDepartmentofGe... 相似文献
225.
地磁扰动与工伤事故之间的相关分析给出,工伤事故的平均发生率与磁情指数Ap成正相关,当磁情指数大于30时,相关系数达0.93,磁情指数从30变到200时,事故平均发生率从0.7增大到1.85。高磁扰日的平均事故发生率最高可达磁静日的2.67倍。作为重要的环境因素的地磁场,当其变化超过人体的可调节范围时,人的机体和行为就要会到明显地干扰,从而导致各类工伤事故的大量增加。 相似文献
226.
227.
We carry out a study of the interaction between electromagnetic fields produced innature and cells with no structure but with different shapes and sizes, considered asapproximations of those observed in the human body. Magnetic fields produced byvarious atmospheric and geomagnetic phenomena are compared with the fieldsgenerated by the cells themselves. Working with frequencies up to 105 Hz, we found that in most cases lightning is the natural phenomena capable of producingfield intensities comparable to those generated by the cells. As a first approximationwe assume that a cell might be affected only if a field of intensity comparable to thecell's field is present. Oscillating fields of less intensity and their harmonics can involveresonant interactions with the cells, however this situation is not considered here. Under the approximation of our study we found that the size and the shape are parameters of paramount importance: lightning represents a natural hazard only for the largest cells, while the quadrangular cells are not affected by any of the natural phenomena considered here. 相似文献
228.
Introduction The occurrence of earthquake has relations not only with seismogenic process of source area,but also with the environment of inner (earth space) and outer (earth-sun space). The varyinggeomagnetic field is natural medium that connects with both factors (DING, 1988). There are two kinds of basic ideas using the diurnal-variation anomalies of the verti-cal-component (Z) in geomagnetic field to predict earthquake. The first kind is local geomagneticanomalies that are obta… 相似文献
229.
Magnetic variation data recorded at 143 sites in the period range of 1000–6000 seconds were used to model the conductance distribution in the eastern part of the Bohemian Massif (BM) and the West Carpathians (WCP). The region represents a contact zone of the Palaeozoic Hercynian and Tertiary Carpathian orogenic systems. Two anomalies in the distribution of the electrical conductivity were found. One with a simple two-dimensional feature is located approximately near the boundary of the Inner and Outer West Carpathians, but the other of a complicated three-dimensional character is at the eastern margin of the BM. We inverted the observed geomagnetic data for the conductance in a unimodal thin sheet embedded at a specific depth. The inversion algorithm minimises the parametric functional that sums the squared norm of the misfit and the stabilising functional, and employs conjugate gradient optimisation. To express the sharp tectonic boundaries, we employed a minimum gradient support functional, which is applied in areas with strong variations of the model parameters. The inversion results confirmed a quasi-linear character of the regional anomaly distinguishing the Carpathian plate and led to new insight into the anomaly over the eastern margin of the BM. According to the results of the modelling the anomaly is formed by several conductive belts intersecting the anomalous zone. These belts follow important faults, dividing the transition zone between the BM and the WCP into individual blocks. 相似文献
230.