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71.
Summary A two-dimensional flow model of an incompressible fluid with constant viscosity has been used to study the changes in the large-scale flow pattern (aspect ratio 4). Implications for convection in the Earth's mantle are discussed.
a ¶rt; mn uuu ua u¶rt;mu nm m unm ¶rt; uu uu mu ama¶rt;a. ¶rt;am mam ¶rt; uu amuu u.
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72.
Summary It is recommended that the data from measurements with supraconducting gravity meters be also analysed with regard to verifying the gravitation absorption hypothesis. Based on theoretical data from a3-year period, the spectrum of the assumed effect of shielding the gravitational influence of the Sun by the Earth's body on the value of the acceleration of gravity has been calculated for the tidal station Brussels (Figs 2a–e).
¶rt;aam aauuam ¶rt;a uu n¶rt;uaumau ma mu u nuunm n¶rt;auaumauu. a mmuu ¶rt;a a mmu nu¶rt; u nm n¶rt;naa ma auauaumau ¶rt;mu a m a uu u u mmu ¶rt; nuu mauu (u. 2a–).
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73.
74.
Summary The thermo-elastic deformations due to the annual temperature variation are computed. The time variation of these deformations is compared with the variation of the slow deformations observed at the tidal station in Vyhne.
u mnu ¶rt;auu, a¶rt; auau mnam nmu a nnmama. ¶rt; mu ¶rt;au a ¶rt; ¶rt; ¶rt;au, u a nuu mauu ().


Dedicated to RNDr Jan Pícha, CSc on his 70th birthday  相似文献   
75.
P. Daněk 《GeoJournal》1993,30(3):249-254
In the 1991 population census, 1.4 million inhabitants of the Czech Republic applied for Moravian or Silesian nationality, which did not exist before.They expressed their consciousness of territorial appurtenance to the historical provinces of Moravia and Silesia and by this declaration they set it above the appurtenance to the Czech nation. New social cleavage thus developed in ethnically almost homogeneous environment of the Czech Republic, which constitutes a potential threat of the further splitting of the State. Trying to find the causes of such a phenomenon, the author deals with the territorial differentiation of these inhabitants and factors which influenced it. The close interconnection with political demands is stressed. The insensive centralizing measures of the communist regime are considered as the direct impulses of the present development. The phenomenon is understood as a specific manifestation of the posttotalitarian social crisis in Central and Eastern Europe.  相似文献   
76.
Relationships among tectogenetic karst types, major morphologic units, and environmental consequences are discussed. The development of urban centers and in-dustrial sites within the Dinaric Karst area without taking into account the above-mentioned parameters, require additional measures. This is necessary in order to avoid the pollution of groundwaters and karst springs used for water development.According to field experience and results of investigations, which were recently published, a reliable geotectonic interpretation needed for distinguishing orogenic and epi-oro-genic (epi-platform) karst terranes has usually been missing in analyses of karst morphology. This is important because the karst morphological features different in origin and distribution can be found in both types, respectively.  相似文献   
77.
Summary On the basis of temperature measurements in 190 boreholes we constructed a map of temperature distribution at a depth of 100 m below the terrain level and maps of temperature gradients in different depth intervals below the Earth's surface in the territory of the Bohemian Massif. Investigations were made into the effects of hydrogeological, geomorphological, structure geological and microclimatic factors on the subsurface temperature field in the Bohemian Massif together with an assessment of effects of these factors on heat flow determinations in shallow boreholes 100 – 200 m deep.
Резюме Нa основaнuu uзмеренuя mемnерamуры в 190 сквaжuнaх былa nосmроенa кaрma рaсnре?rt;еленuя mемnерamуры нa ?rt;лубuне 100 м nо?rt; nоверхносmью Землu u кaрmы ?rt;рa?rt;uенma mемnерamуры в рaзных nо?rt;nоверхносmных uнmервaлaх нa mеррumорuu Чешско?rt;о мaссuвa. Иссле?rt;овaлось осложненuе mеnлово?rt;о nоля у nоверхносmu Землu целым ря?rt;ом фaкmоров: эффекmы рельефa nоверхносmu Землu, ?rt;вuженuя nо?rt;земных во?rt;, mеnлоnрово?rt;носmu ?rt;орных nоро?rt;, мuкроклuмamuческuе эффекmы u ?rt;р. u влuянuе эmuх фaкmоров нa uзмеренuе mеnлово?rt;о nоmокa в не?rt;лубокuх сквaжuнaх (100 – 200 м).
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78.
Summary The paper is intended as a contribution to the quantitative analysis of travel-time curves of seismic events recorded in the Ostrava-Karviná District (OKD). The input data represent a set of 2621 seismic events, recorded by the local seismological network of 26 mine stations DSLA and a regional diagnostic polygon consisting of five surface Lennartz stations. All the events were processed automatically in the Operational Seismological Centre of the Czechoslovak Army Mine in Karviná and stored in the seismological data base. The results are presented in the form of graphs of arrival times versus distance for the whole OKD, for two mines and one tectonic block.Travel-time curves of direct P and S waves, as well as of reflected and refracted waves are given. The direct P and S waves propagate well practically throughout the whole region studied, but their apparent velocities of propagation are affected by the properties of the rock medium.As a result of the complicated geological conditions, the recorded wave image is quite complicated. Methods of mathematical modelling, using kinematic and dynamic parameters of seismic waves, will have to be applied to identify the separate wave groups uniquely.  相似文献   
79.
Summary A general analytical model for travel times of seismic waves propagating in a radially asymmetric Earth, is suggested. It is represented by a series of irreducible spherical tensor products with bipolar spherical coefficients. The main term of the series describes the travel times in a radially symmetric Earth, the others represent corrections due to the spherical assymmetry. The method of least squares is suggested for determining the bipolar spherical coefficients from observed seismic travel times. Since the proposed theory assumes that the analytical representation is related to the reference earth, the corrections to the non-zero focal depth and non-zero sea-level height of the seismographic station must be introduced.
aamuam a aaumua ¶rt; ¶rt;¶rt;aa uu a¶rt;ua ¶rt;¶rt; . mm¶rt;a aam u¶rt; ¶rt;a n¶rt;u m unu uuu uumau. ¶rt;a nuam¶rt;a a¶rt;ua ¶rt;¶rt; . ¶rt;u m aam nna a m a¶rt;ua ¶rt;¶rt;mu. ¶rt;aam un uu uum ¶rt; a¶rt;a¶rt;aa a¶rt;um m¶rt; auu a¶rt;am. ¶rt;aaa mu u¶rt;um u n¶rt;nu -unu¶rt;a u. nuam n ¶rt;u nna n¶rt;mau¶rt;aa, a uu aa u m nm a¶rt;u.
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80.
Summary Four fundamental forms of expansion of the double product of the gravity function into an infinite series are derived. Two isotropic parts are separated, one is expressed by Legendre polynomials and the other by invariants of Wigner's D-matrices.
¶rt; m n¶rt;mau ¶rt; au ¶rt; nu¶rt;uaumau uu ¶rt;. ¶rt; ¶rt; umn amu, na aam n nu a¶rt;a u ma n uauam amu ua.
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