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1.
Normal density earth models   总被引：1，自引：0，他引：1  
Summary Models of the Earth's density, close to thePREM model, have been derived, they reproduce the external normal gravitational field of the Earth and its dynamic flattening, and are referred to as normal density models. The Earth's surface is approximated by an ellipsoid of the order of the flattening, or of its square. Of the group of normal models sgtisfying the solution of the inverse problem, the normal density modelHME2 is recommended. The spherically symmetric density modelPREM, which was corrected in the course of solving the inverse problem, thus creating the modifiedPREM-E2 model, was used as the a priori information.
¶rt; ¶rt;u an¶rt;u nmmu uu ¶rt;uPREM (m. a. a ¶rt;u nmmu), aumau n m u¶rt;mu na¶rt;am auaumau n u. m u annuum am unu¶rt; au. uau amu a ¶rt; mam H==0.003 273 994. ma ¶rt; a ¶rt; ¶rt;m ¶rt;HME2. am anu u a ¶rt; nmmu a unaa ¶rt; a¶rt;ua umua ¶rt;PREM. ¶rt;aam ¶rt;uuau m ¶rt;u n¶rt; aauPREM-E2.
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2.
mam u¶rt;m uu aumuu a m n uamu ¶rt;u nmu umu ¶rt;ua a maum ¶rt;a amu u. a um naa nu nu naama umuu , au a um aumu m n aau umuu mau aum n. aam, m mum au ¶rt;-amu a ma mu aum u u n a aumu m n.  相似文献   

3.
Summary The application of Maslov asymptotic theory in a general 3-D mixed subspace of 6-D complex phase space is proposed to obtain the integral superpositions of Gaussian packets and beams. The ray method and the superposition of plane waves (Maslov method of Chapman and Drummond [7]) are special limiting cases of the above mentioned approach. The same high-frequency asymptotic expansion formulae for seismic body waves were derived previously in [8] using the Gaussian beam method.
uu aunmmu muu aa m a n¶rt;nmam mu a nmama n¶rt; ¶rt; nu uma nnuu a nam u n. nnuu nu u m¶rt; m nuau n¶rt;u au n¶rt; n¶rt;¶rt;a. a amm aunmmuu u a n m¶rt; a n [8].
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4.
Summary Some regularization approaches to downward heat flow continuation from the Earth's surface to the depth of interest are presented, provided the heat transfer is described by the homogeneous steady-state equation. The Fourier transform of horizontal coordinates is used and the relation between the regularization of the heat flow spectrum and the regularization of the heat flow in the spatial domain are discussed. The utilization of an a priori information about the subsurface heat flow is mentioned.
¶rt; m zuau n¶rt;¶rt; n¶rt;u u nmz mnz nma n¶rt;nuu, m n mna nuam ¶rt;¶rt; maua au (au anaa). na naau zuma ¶rt;uam u ama ¶rt; zuau mnz nma u uau z nma. nma m nuu anu u n¶rt;nmz mnz nma.
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5.
Summary The elements of the VLF chorus, observed simultaneously at a ground station and satellite in polar orbit, can be used to determine the differences in the arrival times of waves and their dependence on latitude. Mostly does not change practically over a wide range of latitudes, however, in some cases it may increase appreciably at low value of L. Model computations of the propagation time, based on the assumption that the source of the chorus is located close to the equatorial plane, have indicated the possibility of explaining the increase in at low latitudes by the presence of a step in the electron density profile close to this plane.
a¶rt;u m a u a um nmu nun um nm n¶rt;um amu u nu¶rt;a ma a u u um auum (L). um a a m ¶rt;uana um, m a a¶rt;am aum uu a a L-a. am anmau n¶rt;nuu amua umua naam m um uu a uu uma auu mnu an¶rt;uu m mauu amua nmu.
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6.
Summary For the last two millenia it has been possible to determine the secular variation of solar activity from naked-eye sunspots, aurorae and radiocarbon variations. The results of the analysis of old East Asian observations of comets, which reflect the night cloudiness variation, do not agree with the former findings that the long-term climatic changes derived from comets depend on solar activity. The distinct anticorrelation between the Chinese records of comets and naked-eye sunspots is found only for the period from the 3rd to 6th century A.D., but in other centuries any correlation can hardly be seen. East Asian cometary observations give evidence of climatic changes in different parts of this large geographic region.Secular variations of the River Nile levels, regularly measured from the 7th to 15th century A.D., clearly correlate with the solar variations, which suggests evidence for solar influence on the climatic changes in the East African tropics. The decline of the Kingdoms in ancient Egypt and the occurrence of the Intermediate Periods are generally explained by very low Nile floods and prolonged droughts followed by severe famines and the destruction of the political structure. But the radiocarbon data show that at least the First and Second Intermediate Periods coincide with the secular maxima of solar activity and the Middle Kingdom with the minimum. This contradicts the positive correlation found from the eight centuries of measurements of River Nile levels made by Arabs. It seems that the influence of solar activity on the secular climatic changes has an episodic character.
nu¶rt; uu amumu ¶rt;mam m n¶rt;um nuuum a n¶rt;u ¶rt;a mmu nm au nu n uu u u¶rt;u a nm a¶rt;u¶rt;u uuu. ¶rt; amm nu n uu uu n mmu .. um a m uu ¶rt;a umumuaum n. ¶rt;m auau nu m amum ua a uu amumu a am — am, maau ¶rt;nu¶rt; uamuu uu. ¶rt;a, mam aaua ¶rt;u a¶rt;u m u n a a m am muu ¶rt;au. aua ¶rt;umau anuu ma u u¶rt;u a nma, aum amuu m ¶rt; nu¶rt;a - n 6- , a ¶rt;u nu¶rt;a maa u mmmm. m, aa uu uu mmmu uu ¶rt; ¶rt;au a¶rt;uu m uma, u nuu u¶rt;ummm auuu uu uama au am m au amu.nu¶rt; auauu m n¶rt;a ¶rt; (au), a ma ma aa ma ¶rt; (uu) u n uu, n¶rt;uu u unm ¶rt;u 7- ¶rt; ¶rt;u 15- a, n¶rt;u auau. m u¶rt;ummm uuu a a uamuu uu m-auau mnua. a u u numu aumu ¶rt;unmu am m au ua nuaa. na¶rt; ¶rt;unmu am u amnu ¶rt;amu m uu ¶rt; u u n¶rt;umu aau, a mu n¶rt;a m¶rt; u au numu mm. ¶rt;a, n a¶rt;u¶rt; ¶rt;a aum, m n a n u m ¶rt;amu na¶rt;am ¶rt;umu auau amumu, m nmuum num uu, ¶rt; u ummu uu ¶rt; u. am, m uu amumu a uu uama um aa nu¶rt;u aam.
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7.
ma n n¶rt;u u¶rt; u, m um u umuu ¶rt; amaa n nu , a¶rt;a n n a m. am nua ¶rt;a aau a¶rt;u n uumaa u ummna a ¶rt;u amuu 1965–1970 . mama u¶rt;, m na an amua ¶rt;mam ¶rt; m, m um n¶rt;um ¶rt;mam mm.  相似文献   

8.
Summary The paper is concerned with the properties of a density distribution within the Earth. A system of density parameter constraints involving Stokes' coefficients of the gravity field and the parameters describing the Earth's figure is derived. A density model, whose parameters fit these constraints, accounts for the fine structure of the gravity field and Earth's figure. Additional condition imposed on the average spherical density model are derived; they guarantee that the average spherical model is compatible with the 3-D density model.
aamuam ma an¶rt;u nmmu mu u. ¶rt;a uma u, auuau au naam nmm ¶rt;u; uma am m naamaumau n u naam nuau u u. mma ¶rt;, naam m ¶rt;mm mu auuau u, nm n¶rt;um uu umnmau m mmaumau n u u u. ¶rt; ma ¶rt;num u, aa¶rt;au a ¶rt; u ¶rt; nmmu, m nuam ¶rt;uu ¶rt; u ¶rt;u m nmm ¶rt;.
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9.
Summary The theory of methods of computing single- and inter-station transfer functions in both the spectral and time domains was developed in paper[1]. Both approaches are applied to the variation data recorded at field stations along two non-simultaneous profiles traversing the eastern margin of the Bohemian Massif, where a zone of anomalous induction seems to mark an important geological boundary of formations with different histories of development. The results of both analyses are found to coincide within reasonable bounds of 20–30% in the principal induction characteristics.
u m¶rt; ama ¶rt;-u -mau n¶rt;am u nma u am a ua am[1]. am nua m am a n¶rt;¶rt;a nu ¶rt; aaua ¶rt;aaum auau aumua a n mau ¶rt; u nu, nau m au aua,¶rt; aa a aa u¶rt;uu. a, u¶rt;u, mamau a¶rt;a ¶rt; ¶rt; ¶rt;uuau au umuu aumu. mam aau nma u am auam a 20–30% ¶rt; u¶rt;u naam.
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10.
Summary The magnetovariational data of 143 stations distributed over the eastern margin of the Bohemian Massif, over the Brunovistulicum and the West Carpathian sector were analysed to obtain transfer functions of the geomagnetic field. Methods of multivariate coherence analysis (spectral domain approach) and of impulse response (time domain approach) were employed. Complex induction vectors were estimated and contour maps of transfer functions were computer generated. Analysing their spatial distribution, we mapped the zones of anomalous induction and interpreted them in terms of electrical conductivity structure with its tectonic implications.
azumauau ¶rt;a 143 n mau an n amu m au z aua, az a umua u ana anam auma n¶rt;am uu zazumz n m¶rt;au zz zmz aaua (nma n¶rt;¶rt;) u unz mua um ( n¶rt;¶rt;). mu mama n u¶rt;u ma u nm am uuu n¶rt;am u. au nmamz an¶rt;u mu aamumu m aa u¶rt;uu, ¶rt; mm ¶rt;uu u n¶rt;a u zz-zuua umnmau.

Contribution No. 105/90, Geophysical Institute, Czechosl. Acad. Sci., Prague.  相似文献   

11.
Summary Determination of the gravitational effect of some bodies, the density of which is supposed to be variable in the vertical direction, possibly in the horizontal direction, too.
n¶rt;uaumau ma m m, nmm m um mua uu muma anau.
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12.
a 27 nu amu ama m¶rt;au nma aaua ¶rt; nu nma anum¶rt; 27-¶rt; auauu u ÿeau nu¶rt;au 13–14 u 9 ¶rt;. mam an¶rt;u nma anum¶rt; Z u H mau a n nuuuu auauuu uuP 1 (cos ) u P 1 /, mmm. mau mau a um auumu mau auau ¶rt; mmu mu Z/H ¶rt; a¶rt; amuu. au ¶rt; mmuuu u umu a¶rt;au muu ¶rt; ¶rt;am uau mu ¶rt;¶rt;mmu mu u. a aaua au mu Z/H ¶rt;m u uam n u m aa amu.  相似文献   

13.
Summary The method of numerical modelling of ionospheric filtration of the Fourier components of a signal from the frequency range of Pc1 micropulsations is employed in the spectral analysis (frequency f, angle of incidence ) of the relative characteristic of the amplitude and energy reflectivity of the ionospheric layer with respect to ordinary Alfvén modes incident in the meridional plane. The results are presented for four different models characterizing the midlatitude day- and night-time ionosphere under low and high solar activity. The results indicate the specificity of filtration of ordinary Alfvén waves. It is proved that the lower region of the modelled ionosphere, as part of the midlatitude ionospheric wave guide (in particular the F2 layer), behaves like an Alfvén resonator in the given spectral range.
m¶rt; u ¶rt;uau u umauu -mau uaa u amm ¶rt;uanaa unau 1 n¶rtum nma aau (amma f, a¶rt;u ) mum anum¶rt; u mu maamu u ¶rt; ¶rt; a, a¶rt;au a u u¶rt;ua nmu. mam n¶rt;aam ¶rt; m a ¶rt; ¶rt;um m ¶rt; u u nu u u nu amumu. aam nuum umauu a. naa, m ua am ¶rt;ua u (a am F2-u ¶rt;um ¶rt;a) ¶rt;m nma ¶rt;uana a am a.
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14.
m m n¶rt;u mamu [7] m aa uu u aa a¶rt;u uu. uau ¶rt; u m¶rt;mu uu u u, a ¶rt;, u mu n nm. ¶rt;um a ama, ma m u¶rt; nm ¶rt; au ¶rt;amma m um. auu mamu ¶rt;um uua aa ¶rt; m unu¶rt;.  相似文献   

15.
Summary An attempt is made to show possible ways of predicting radio wave absorption in the midlatitude lower ionosphere using relations between absorption and the intensity of solar ionizing radiation and/or common solar activity indices, and between absorption and f0F2.
aa mu nuau nu a¶rt;u ¶rt;um u u a mu ¶rt; nu u umum uuu uu (uu uu u¶rt;au amumu) u ¶rt; nu u f0F2.
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16.
Summary The optimization of the method of determining the addition constant of an EDM is discussed. The advantages of the optimization procedure from the point of view of efficiency and improvement of accuracy are reported.
nuuu ¶rt; n¶rt;u a¶rt;¶rt;uu n ¶rt;. u nu n u uu u nu u.
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17.
u nu m¶rt;a a u u¶rt;a ¶rt;a muna nua a n umu mnuu ua.

Dedicated to Academician Alois Zátopek on His 65th Birthday  相似文献   

18.
Summary This paper considers a number of questions concerning the interpretation of infrared pictures of the earth taken from space. Long period mean statistical values of the contrasts in radiation temperature between the earth's surface and clouds for a number of points in the U.S.S.R. in different seasons have been calculated which makes it possible to conclude when and where clouds against the underlying surface can be detected as well as to formulate the requirements which the instruments mounted on a satellite are to satisfy. The blackness coefficients of clouds at different layers have been theoretically determined, the investigation of the problem of the spectral regions selection for satellite observations has been conducted. The worked out calculation scheme has been used in the solution of the problem of the possibility of satellite detection of such thermal non-homogeneities as sea currents and jet streams in the atmosphere. Examples of the synoptical analysis of the infrared pictures of the cloud cover obtained with the help of the NIMBUS-1 and COSMOS-122 satellites have been considered. , . , , , , . , . , , . , -1 -122.  相似文献   

19.
Summary The effect of an irregular contact of two different rock types on the surface heat flow was analysed for the Zlatý Kopec region in northwest Bohemia. The 2-D geothermal model of subsurface structures was compiled according to measured values of the thermal conductivity and heat sources and by using isobaths map of the metamorphite-granite boundary. The heat flow was computed numerically from the temperature distribution obtained as a finite-difference solution of the heat conduction equation. It was found that the heat flow variation, corresponding to the most probable model, amounts approximately to the half of the actually observed changes. The surface heat flow is affected strongly by the thermal conductivity contrast between the overlying metamorphites and underlying granites and, on the contrary, it is little sensitive to the heat production difference between both rock types. It seems, therefore, that, despite the big heat production contrast observed, the main source of the heat flow variability are thermal conductivity inhomogeneities.
¶rt;am uu mama ¶rt; m¶rt; mun n¶rt; a nm mn nm ¶rt; amu am n ana¶rt; uu. a u au mnn¶rt;mu u mnauu u n amu aauauaum — mauu n¶rt; a maa ¶rt;a ¶rt; nunm mm. n nm auma n -am u au mnn¶rt;mu. mam ¶rt;m, m auau mn nma ma a m ¶rt;u, n¶rt;mam nuuum nu a¶rt;a uu. a nm m u um aua mnn¶rt;mu ¶rt; aauu mauuu n¶rt;au u uaauaum, u am, nm a mum auu mnauu ¶rt; muu n¶rt;au. aum, m, m a a¶rt;a au mnauu,a umu auau mn nma m ¶rt;¶rt;mu uma mnn¶rt;mu.
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20.
Summary Determining magnetic parameters of rock samples by means of an astatic magnetometer is essentially solving a certain kind of the inverse problem. If the sample is measured at small distances from the astatic system, or if the sample is magnetically strongly inhomogeneous, the problem of higher order magnetic moments becomes more difficult. The accuracy of estimating the parameters depends on the correctness and the comprehensiveness of the model chosen. In the present paper a statistical model is proposed, which solves satisfactorily the problem of measuring the magnetic parameters of a generally magnetized sample provided the remanent moment distinctly dominates over the induced moment.
n¶rt;u a¶rt;muu naam a ¶rt; n¶rt; nu nu amamu¶rt; a¶rt;umma, mu, n¶rt;mam u n¶rt;¶rt; ¶rt;a am a¶rt;au. u a um uu amamu um uu u a muu a¶rt;mua u ¶rt;¶rt;, m a¶rt;um m u n¶rt; amm. m n¶rt;u naam auum m mmu u nm a ¶rt;u. ¶rt;a am n¶rt;a¶rt;am mamumua ¶rt;, ma ¶rt;mum am n uu a¶rt;muu naam u a aa¶rt;u a nu uu, ¶rt;¶rt;a m mam aa¶rt;umu aum na¶rt;am a¶rt; u¶rt;ua m.
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