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1.
Summary Tests on the vertical vibrating table in the frequency range of70–110 Hz indicate that quartz gravity meters are10–100 times more sensitive at some frequencies than under low-frequency excitation. At high frequencies, the reading beam is at rest and deflected from the correct position. Slow fluctuations of amplitude and frequency near resonance could cause slow irregular motion of the beam with absence of low-frequency ground motion of sufficient intensity.
unmauaum a mua um¶rt; ¶rt;uana amm 70–110u mam, m a m ammaaum 10–100 a mum nu uamm au. u amm au u a¶rt;um n m mu m nu. ¶rt; auauu anum¶rt; u amm au uu aa m am uamm u ua ¶rt;a mmmm uamm au n ¶rt;mam umumu.
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2.
Résumé On commence par définir le creusement et le comblement d'une fonctionp(, t) du tempst et des points (, ) d'une surface régulière fermée en se donnant, sur cette surface, un vecteur vitesse d'advection ou de transfert tangent à . Le creusement (ou le comblement) est la variation dep sur les particules fictives se déplaçant constamment et partout à la vitesse , A chaque vecteur et pour un mêmep(, ,t) correspond naturellement une fonction creusementC (, ,t) admissible a priori; mais une condition analytique très générale (l'intégrale du creusement sur toute la surface fermée du champ est nulle à chaque instant), à laquelle satisfont les fonctions de perturbation sur les surfaces géopotentielles, permet de restreindre beaucoup la généralité des vecteurs d'advection admissibles a priori et conduit à des vecteurs de la forme: , oùT est un scalaire régulier, () une fonction régulière de la latitude , le vecteur unitaire des verticales ascendantes etR/2 une constante. Ces vecteurs sont donc une généralisation naturelle des vitesses géostrophiques attachées à tout scalaire régulier. Dans le cas oùp(, ,t) est la perturbation de la pression sur la surface du géoïde, le vecteur d'advection par rapport auquel on doit définir le creusement est précisément une vitesse géostrophique: on a alors ()=sin etT un certain champ bien défini de température moyenne.On déduit ensuite une formule générale de géométrie et de cinématique différentielles reliant la vitesse de déplacement d'un centre ou d'un col d'un champp(, ,t) à son champ de creusementC (, ,t) et au vecteur d'advection correspondant. Cette formule peut être transformée et prend la forme d'une relation générale entre le creusement (ou le comblement) d'un centre ou d'un col et la vitesse de son déplacement, sans que le vecteur d'advection intervienne explicitement. On analyse alors les conséquences de ces formules dans les cas suivants: 1o) perturbations circulaires dans le voisinage du centre; 2o) perturbations ayant, dans le voisinage du centre, un axe de symétrie normal ou tangent à la vitesse du centre; 3o) évolution normale des cyclones tropicaux.Finalement, on examine les relations qui existent entre le creusement ou le comblement d'un champ, le vecteur d'advection et la configuration des iso-lignes du champ dans le voisinage d'un centre.Ces considérations permettent d'expliquer plusieurs propriétés bien connues du comportement des perturbations dans différentes régions.
Summary The deepening and filling (development) of a functionp(, ,t) of the timet and the points (, ) of a regular closed surface is first of all defined, in respect to a given advection or transfer velocity field tangent to , as the variation ofp on any fictitious particle moving constantly and everywhere with the velocity . For a givenp(, ,t) and to any there corresponds a well defined development fieldC (, ,t). All theseC fields are a priori admissible, but a very general analytical condition of the perturbation fields in synoptic meteorology (the integral of the development fieldC (, ,t) on any geopotential surface vanishes at any moment), leads to an important restriction to advection vectors of the form: , whereT is any regular scalar, () any regular function of latitude, the unit vector of the ascending verticals andR/2 a constant. These vectors are a natural generalisation of the geostrophic velocities attached to any regular scalar. Whenp(, ,t) is the pressure perturbation at sea level, its development must be defined in respect to a geostrophic advection vector belonging to the above defined class of vectors with ()=sin andT a well defined mean temperature field.A general formula of the differential geometry and kinematics ofp(, ,t) is then derived, giving the velocity of any centre and col of ap(, ,t) as a function of the advection vector and the corresponding development fieldC (, ,t). This formula can be transformed and takes the form of a general relation between the deepening (and filling) of a centre (or a col) of ap(, ,t) and its displament velocity, the advection vector appearing no more explicitly. A detailed analysis of the consequences of these formulae is then given for the following cases: 1o) circular perturbations in the vicinity of a centre; 2o) perturbations having, in the vicinity of a centre, an axis of symmetry normal or tangent to the velocity of the centre; 3o) normal evolution of the tropical cyclones.Finally, the relations between the developmentC (, ,t) of a fieldp(, ,t), the advection velocity vector and the configuration of the iso-lines in the vicinity of a centre are analysed.These theoretical results give a rational explanation of several well known properties of the behaviour of the perturbations in different geographical regions.


Communication à la 2ème Assemblée de la «Società Italiana di Geofisica e Meteorologia» (Gênes, 23–25 Avril 1954).  相似文献   

3.
Summary The changes in the anisotropy of initial susceptibility of haematite ores, induced by a D.C. magnetic field are studied. After applying stronger magnetic fields, the changes in the anisotropy parameters are considerable and depend on the manner in which the basal planes of the haematite grains are arranged in the samples. The experimental results are interpreted on the basis of the single-domain theory. The proposed simple model of induced anisotropy is based on the relation between the directional susceptibility of the sample and the preferred orientation of the magnetic moments of the grains in polycrystalline haematite.
am uu aumnuu aa nuuumuamum ¶rt;, a nm aum n. nuu u aum n uu aumnuu aam u aum m na n¶rt;u nmamum aa. numa. ¶rt;a umnmua unau ¶rt;¶rt; muu. ¶rt;a nma ¶rt; a aumnuu aa a auumu u nuuumu m umauu aum m nuumauamum.


Presented at the 5th Scientific Assembly of IAGA in Prague 1985.  相似文献   

4.
a aam u¶rt;au m ua aum aauu nu¶rt;u ¶rt; u anam a ¶rt;mu uu mu amuma n nu aum nuuumu num a¶rt;a uu ma¶rt;uuma, a m um ¶rt;u n u-a nummu ¶rt;¶rt;. num naau, m mua n¶rt;um nu¶rt; u ma aamam. a n¶rt;a umnmau aauuu u a mumuu m auu,¶rt; umuu n aaumu u mu n¶rt;umu m uam au u a mam ¶rt;u n n¶rt;a.  相似文献   

5.
Summary Secular non-tidal variations of geopotential and gravity are estimated due to secular decrease of the second zonal geopotential harmonic, secular polar motion and deceleration of the Earth's rotation.
am a nuu uunmuaa u u u mmu, a u m aauunmuaa, ¶rt;uu n u u mu au u.
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6.
Summary Radiation absorption by water vapour plays an important role in the physics of the atmosphere. The calculation of the absorbed radiation energy by water vapour requires the amount of precipitable water in the atmosphere to be known. Actinometric and aerological measurements were used to establish the relation between vapour pressure and absorbed solar radiation.
u a¶rt;uauu ¶rt; nam uam a amu uuu am. uu n a¶rt;uauu ¶rt; na a¶rt; am m a¶rt; ¶rt; am. u¶rt; mu ¶rt; ¶rt;au ¶rt; naa u n a¶rt;uau a amu muu u auu uu.
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7.
Summary The vertical distribution of the contribution of the energy flux density due to the Alfvén(ordinary) wave, guided by the geomagnetic field(and propagating through the ionosphere to the Earth's surface) in the horizontal direction is demonstrated in the mechanism of the horizontal propagation of the Pc1 signal. The distribution with height is shown of the variations of the polarization characteristics of the propagating wave(e.g. the rotation of the polarization plane, changes in ellipticity, attenuation, etc.), which are the result of coupling in the denser layers of the low ionosphere in which also suitable isotropic(extraordinary) modes are generated. The results obtained using the method described in[4, 13] are demonstrated on a model of the daytime ionosphere under incidence of ordinaryL-modes, frequency f=0.3 Hz, and various meridional angles at the ionosphere.
auauma anmau uaa Pc1 naa m an¶rt;u ¶rt;u nmmu ma uu uma anauu maum n n¶rt; , anma u nmu. naa m an¶rt;u uu aamumu nuauu anma (nauau nmu nuauu, uu unmumu, amau u m.¶rt;.), m m ¶rt;mu au¶rt;mu na uu u . ¶rt; mum n¶rt;¶rt;u umn() ¶rt;. mam num m¶rt; [4, 13] ¶rt;mua ¶rt;u ¶rt; u nu na¶rt;uu a u L-¶rt; amm f=0,3 n¶rt; au u¶rt;uau au.
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8.
Summary The area of the Upper Silesian Coal Basin was characterized by generally high heat flow ranging from 60 to 120 mWm–2, mean 82±16 mWm–2, which has been difficult to explain. Therefore all published data on the heat flow in this region (n=37) were summarized and re-evaluated. Special attention was paid to the detailed assessment of the lithological structure and the contribution of the individual rock types to the characteristic in-situ thermal conductivity. Also the thermal conductivity of the coal bearing layers was estimated and its effect on the temperature-depth distribution was investigated. The application of the data obtained for the representative thermal conductivity profiles of the whole drilled section considerably reduced the mean heat flow to 70±8 mWm–2. The latter value is fully compatible with the tectonic structure of the northern part of the Carpathian Frontal Foredeep. Slightly increased geothermal activity compared with the heat flow field of the adjacent part of the Bohemian Massif corresponds to certain deep geological rejuvenation during the creation of the Western Carpathians.
a -uu aa aamum nu uuau mn nma (m 60 ¶rt; 120 m.–2 nu ¶rt; 82±16 m. –2), m ¶rt;a ¶rt u. m u u nm a nua ¶rt;a mn nma (n=37) ¶rt; ¶rt;a ua. ua ¶rt; ¶rt;ma aau umuu aa u u mnn¶rt;mu in situ ¶rt; a¶rt; muna n¶rt;. a a mnn¶rt;m m, a ma, a ma u¶rt;aa an¶rt;u mnam nu. nau n mam ¶rt; nuau mnn¶rt;mu m u amu aa nu am uum ¶rt;u mn nm ¶rt; 70±8 m.–2. a uua n mam mmu u amu anam a nua. m uumu amumu n au mn n nuaa amu aua mmmmuuau amuuauu nu uauu um ana¶rdt; anam.
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9.
am mam mauau m amaua aaum CG-2¶rt;u muna No; 174-G, 181-G u 228-G nuu m¶rt;a aa. mama mauau aum, m num mum mm 1. 10–4 u n¶rt;um um a. a a¶rt;a ¶rt; a auum ama uum mauaum m mnam.  相似文献   

10.
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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11.
Summary The theory of the multivariate coherence analysis(spectral domain approach) is developed for calculating single- and inter-station transfer functions and corresponding vector induction characteristics from time variations of the geomagnetic field components. An alternative approach of calculating similar induction characteristics using a time domain algorithm is shown.
aam mu m aaua(nma n¶rt;¶rt;) nuuu ama ¶rt;-u -mau n¶rt;am u u mmmu m aamumu u¶rt;uu n anua auau mau aum n u. u¶rt;um ma m¶rt; u aau aamumu u¶rt;uu nm ama amu un mua um. nuam aum na auu am u aamum ¶rt; n ama naam.
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12.
Summary The effectiveness of recording seismic phenomena in the Kruné hory (Mts.) region in NW Bohemia by selected stations in the CSR, GDR and Poland has been estimated. Magnitude isolines of the weakest earthquakes, which can be localized and detected with an 0.9 probability, were calculated on the basis of the level of seismic disturbances at the individual stations and of the empirical dependence of the attenuation of seismic waves with distance.
a a mum umauu uu u amu ¶rt; ana¶rt; uu uau mauu a mumuu , u a a uu n a m¶rt; mau u nuu auumu amau uu m amu u auma uuuu aum¶rt; a a mu, m mm 0.9 auuam u aum.
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13.
Summary The four primary geodetic parameters defining the geodetic reference system are discussed from the point of view of their physical meaning and current estimation of their actual accuracy. The geopotential scale factor has been treated as the primary geodetic parameter defining the Earth's dimensions.
¶rt;am m nu¶rt;uu naama, n¶rt;u¶rt;u um mumu, mu u uu a u mmu. ama amnmuaa ¶rt;am am nu¶rt;u naama, n¶rt; a u.
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14.
Summary A model, explaining the effect of air pressure changes in the space of the measuring system on the fine dial counter constant of the Worden and similar gravity meters, is presented. It is based on the changes of the bellows volume with compensating the gravity changes. It is shown that the resetting the gravity meter in the whole range has practically no influence on the fine dial counter constant.
u¶rt;a ¶rt;, na m uu ¶rt;au ¶rt;a nmam uum um a nm a umaauma ¶rt; u nuaum. ¶rt; aa a uu a ua umu uma nu nauu uu u mmu. aa, m nma ¶rt;uanaa um namuu um a uu nm a uma.
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15.
Summary The geographical distribution of organic matter and particles <20 m in North Sea sediments as well as the correlation between organic content, <20 m fraction and PCB (as the sum of content of 24 individual components), p, p-DDE, HCB, -HCH and Lindane (-HCH) is reported. High amounts of organic matter and fine particles have been found in Fladen Ground, Kattegat/Skagerrak/Norwegian Channel, and the inner German Bight. Organic matter settling in the Kattegat/Skagerrak/Norwegian Channel is probably degraded by benthic organisms, including mineralization by bacteria. The smelter in south Norway and the rivers Ems and Elbe are point sources for HCB, the mud-area south-east of Helgoland is a point source for HCB and PCBs. No point source, however, was found for p,p-DDE. Sediment content of PCB, p,p-DDE and HCB show a good correlation to the amount of organic matter and to the <20 m fraction. -HCH and Lindane are only poorly adsorbed onto sediments.
Zyklische organische Chlorverbindungen in Nordseesedimenten: Verteilung von organischer Substanz und feinpartikulärem Material
Zusammenfassung Es wird über die Verteilung von organischer Substanz und feinpartikulärem Material <20 m in Nordseesedimenten sowie über die Korrelation der Sedimentparameter mit den Konzentrationen von polychlorierten Biphenylen (24 Einzelisomere), p,p-DDE, HCB, -HCH und Lindan (-HCH) berichtet. Hohe Gehalte an organischer Substanz und der <20 m Fraktion wurden im Fladengrund, Kattegat/ Skagerrak/Norwegische Rinne sowie in der inneren Deutschen Bucht gefunden. Die Ergebnisse legen den Schluß nahe, daß ein Großteil des sedimentierten organischen Materials vor der norwegischen Küste von Benthosorganismen und Bakterien verstoffwechselt wird. Durch die mit Søderbergelektroden arbeitenden Metallschmelzen Südnorwegens sowie durch die Flüsse Elbe und Ems werden die Sedimente punktuell mit HCB belastet. Das Schlammgebiet südöstlich von Helgoland tritt als Emittent für PCBs in Erscheinung. Für p,p-DDE konnte keine Punktquelle nachgewiesen werden. Im Gegensatz zu -HCH und Lindan korrelieren die Sedimentkonzentrationen an PCBs, HCB und p,p-DDE gut mit den Gehalten an organischer Substanz bzw. feinpartikulärem Material.

Les Organochlorines cycliques dans les Sédiments de la Mer du Nord, relation avec la taille et les matières organiques
Résumé La distribution géographique de matière organique et des particules de taille inférieure à 20 m dans les sédiments de la Mer du Nord ainsi que la corrélation entre le contenu organique, (la fraction <20 m) et PCB (somme des contenus de 24 composants individuels), p, p-DDE, HCB, -HCH et Lindane (-HCH) est décrite. D'importantes quantités de matières organiques et de particules fines ont été trouvées à Fladen Ground, Kattegat/Skagerrak/Norwegian Channel et dans le baie intérieur allemende. Les composants organiques qui se trouvent dans le Kattegat/ Skagerrak/Norwegian Channel sont probablement soumis à la dégradation par des organismes (benthic), et aussi à une minéralisation par bactéries. Les usines de métallurgie du Sud de la Norvège et la rivière l'Ems et l'Elbe sont des points sources pour HCB, les zones de boue au Sud Est de Helgoland sont des points sources pour HCB et PCB. Aucun point source ne fût trouvé cependant pour p, p-DDE. Le contenu en sédiment de PCB, p, p-DDE et HCB montre une bonne corrélation avec la quantité de matière organique et la fraction <20 m. -HCH et Lindane ne sont que peu absorbés dans les sédiments.
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16.
Summary Teleseismic P residuals calculated for waves arriving from various azimuths and angles of incidence, and a 3-D inversion of the residuals provided the basis for characterizing the uppermost mantle structure beneath Bulgaria. The Moesian Platform and the Rhodopean Massif are two different blocks characterized by a lithosphere thickness of about 130–140 km with a zone of lithosphere thinning along their contact. Both units have opposite patterns of the directional dependence of relatively high and low P velocities. This directional dependence is interpreted by dipping anisotropic structures in the subcrustal lithosphere, which probably represent remnants of paleosubductions of an old oceanic lithosphere.
auma u nu¶rt;u n¶rt; au aumau u au. a uu mu ¶rt;am ¶rt; aamuauu mm amuu n¶rt; au. uua nama u ¶rt;nu au, ¶rt;a au a mu um nuuum 130–140 ¶rt; uma m ¶rt; u mama. a a aamua nmun ana auum mum u u mu . ma anaa auum umnmuaa a nu aumn mm amu. mu mm n¶rt;maum a mamu na¶rt;u ma au um.
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17.
nua m¶rt; nma aaua a, umua m nma, m n¶rt;um umau nuau un nmam. m¶rt; annua aaum nauu Pi2 u Pc3 u amu u u ¶rt;. ¶rt;a ma m ¶rt; nmam nuau aamumu u u auum m aum amumu.  相似文献   

18.
a¶rt;a ma nu an u u (SID) u nu n a (a n¶rt; au) mu 1965–1975 . u u SID na¶rt;am nau, mum u nm R.  相似文献   

19.
Summary The secular positive acceleration of the Earth's rotation has been computed on the basis of the observed secular decrease of the second zonal harmonic[5]. It corresponds to the observed secular deceleration of the Earth's rotation which should be greater because of oceanic tides.
¶rt; u a¶rt;a u m aauu [5], u ¶rt;a num u au. m mmmu a¶rt;a u mu au u, m.. n¶rt; n m uu , ¶rt; m n auu nuua.
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20.
Summary An algorithm is presented for solving the problem of electromagnetic induction in a halspace with a 3-D perturbing body under a harmonically variable exciting field. There are analysed properties of the Green's tensor function elements as well as their integrals in elementary prismatic volumes into which the body is divided. The results, obtained from numerical computations, are given for a long highly conducting prism, which is one of the models in the COMMEMI project.
¶rt; azum u a¶rt;au mazum u¶rt;uu ¶rt; zauu nz ¶rt;az n nnmam m au m. ¶rt;a ma m m uu n ma a, a m a¶rt; a m. nu uu mam mm nm, n¶rt; nu, ¶rt; u ¶rt; nma COMMEMI.
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