搜索结果: 1-15 共查到“地球物理学 Low-frequency”相关记录18条 . 查询时间(0.145 秒)
High resolution electromagnetic methods and low frequency dispersion of rock conductivity
electromagnetic sounding induced polarization frequency dispersion of conductivity resolution of sounding mathematical modelling
2015/10/8
The influence of frequency dispersion of conductivity (induced polarization) of rocks on the results of electromagnetic (EM) sounding was studied on the basis of calculation of electric field of verti...
The temporal and spatial variations of low frequency geomagnetic pulsations at polar cusp and cap latitudes
Geomagnetic pulsations Antartica
2015/10/8
Geomagnetic field measurements at two Antarctic stations are compared during two weeks in the local summer (January 1-15, 1992). Low frequency (0.6-6 mHz) pulsations are observed at each station near ...
Low-frequency (0.7-7.4 mHz) geomagnetic field fluctuations at high latitude:frequency dependence of the polarization pattern
Geomagnetic pulsation MHD waves and instabilities wave polarizations Antartica
2015/9/28
A statistical analysis of the polarization pattern of low-frequency geomagnetic field fluctuations (0.7-7.4 mHz) covering the entire 24-h interval was performed at the Antarctic station Terra Nova Bay...
Local time behaviour of low frequency geomagnetic field fluctuation power at low latitude
Geomagnetic pulsation MHD waves and instabilities
2015/9/28
In this paper we present a statistical study of the local time behaviour of low frequency (0.7-4.0 mHz) geomagnetic field fluctuation power at a low latitude station (corrected geomagnetic latitude 36...
Low frequency geomagnetic field fluctuations at cap and low latitude during October 29-31,2003
magnetospheric ULF waves sun-earth interaction polar cap
2015/9/2
On October-November 2003 complex interplanetary structures, originated by a series of solar eruptions, hit the Earth, triggering violent Sun-Earth connection events. In this paper we analyze the low f...
Slow earthquakes and low frequency tremor along the Apennines,Italy
Slow earthquakes Tremor Apennines
2015/9/1
This paper reviews the main observations on slow earthquakes and low frequency tremor made along the Apennines,the main seismic active zone of Italy. These observations have been made using a geodetic...
Effects of solar and geomagnetic activities on the sub-ionospheric very low frequency transmitter signals received by the DEMETER micro-satellite
Solar and geomagnetic activities Pre-seismic electromagnetic emissions
2015/8/24
In the framework of seismic precursor electromagnetic investigations, we analyzed the very low frequency (VLF) amplitude signals recorded by the Instrument Champ Electrique (ICE) experiment on board t...
Possible precursor to the March 11, 2011, Japan earthquake: ionospheric perturbations as seen by subionospheric very low frequency/low frequency propagation
Earthquake predictio Ionospheric perturbatio VLF/LF propagation
2015/8/24
This study reports on a possible very low frequency/low frequency (VLF/LF) subionospheric precursor to a recent earthquake in Japan. As the epicenter of this large Japanese earthquake on March 11, 201...
Solar wind low-frequency magnetohydrodynamic turbulence:extended self-similarity and scaling laws
Solar wind low-frequency magnetohydrodynamic turbulence extended self-similarity scaling laws
2009/11/16
In this paper we review some of the work done in investigating the scaling properties of Magnetohydrodynamic turbulence, by using velocity fluctuations measurements performed in the interplanetary spa...
A simple nonlinear model of low frequency (interseasonal) oscillations in the tropical atmosphere
nonlinear model low frequency oscillations tropical atmosphere
2009/11/16
In this paper, for a prescribed normalized vertical convective heating profile, nonlinear Kelvin wave equations with wave-CISK heating over equatorial region is reduced to a sixth-order nonlinear ordi...
An example of resonances,coherent structures and topological phase transitions-the origin of the low frequency broadband spectrum in the auroral zone
coherent structures topological phase transitions low frequency broadband spectrum auroral zone
2009/11/12
We consider the phenomena of intermittent turbulence in magnetized space plasmas from the point of view of topological phase transitions involving the merging and interactions of anisotropic coherent ...
Low-frequency variability in idealised GCM experiments with circumpolar and localised storm tracks
Low-frequency variability idealised GCM experiments circumpolar localised storm tracks
2009/11/12
Idealised global circulation model simulations with circumpolar and localised (one and two) storm tracks are re-analysed to determine scaling, intermittency and phase-space structures. In a hundred ye...
Low-frequency linear waves and instabilities in uniform and stratified plasmas:the role of kinetic effects
Low-frequency linear waves uniform and stratified plasmas kinetic effects
2009/11/11
We review the basic approximations underlying magnetohydrodynamic (MHD) theory, with special emphasis on the closure approximations, i.e. the approximations used in any fluid approach to close the hie...
The strange physics of low frequency mirror mode turbulence in the high temperature plasma of the magnetosheath
strange physics low frequency mirror mode turbulence high temperature plasma
2009/11/11
Mirror mode turbulence is the lowest frequency perpendicular magnetic excitation in magnetized plasma proposed already about half a century ago by Rudakov and Sagdeev (1958) and Chandrasekhar et al. (...
Continuous partial trends and low-frequency oscillations of time series
Continuous partial trends low-frequency oscillations time series
2009/11/9
This paper presents a recent methodology developed for the analysis of the slow evolution of geophysical time series. The method is based on least-squares fitting of continuous line segments to the da...