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1.
Summary The Gaussian beam method is applied to vertical seismic profiling in 2-D and 3-D models. A simple approach to the computation of Gaussian beam seismograms in the vicinity of structural interfaces is proposed. The effects of (a) the radiation pattern of a point source, (b) noncausal attenuation, (c) transverse inhomogeneities in synthetic seismograms are studied on numerical examples.
m¶rt; a n unm ¶rt; mua u nuuau ¶rt; u m ¶rt; ¶rt;. nmm n¶rt;¶rt; am a mmu mm a¶rt;a. a nua ummuu a uam m (a) uu m umua, () nu nu u () nn ¶rt;¶rt;m.相似文献
2.
u¶rt;m n uu ¶rt;u m n u ma n¶rt;aa, nu m¶rt;u u ¶rt;uau. n nuu uu ¶rt;u m n ¶rt;a¶rt; nu NoNo VI, VII. u au u n m a
(x, H), ¶rt;auu an¶rt;u ¶rt;u m ¶rt; m¶rt; nu, u mua m nuu
(H), aamuu an¶rt;u m a mua ¶rt;¶rt; uu ¶rt;uua u a. u a ¶rt;u m
(x, H) amm ¶rt;uuu (u) a m¶rt; nu. m¶rt; u, auuu aau, om aamuam muau an¶rt;u ¶rt;u m, uu , n m u m nu aamuu a nmu, am ma a¶rt;am aa uu ¶rt;u m. aa u a¶rt;u n nu NoNo VI u VII u umuu ¶rt;a. mua m nu
(H) num m ¶rt;u amu aua u anam um, ¶rt;a amu ¶rt;aua u ¶rt;- nma (nu No VII). ma ¶rt; ¶rt; aua, maa numa nm m u numa nm ma¶rt;um, a unaa nuu umnmauu a¶rt;uu ¶rt;uau amu aua. 相似文献
3.
a mmuu ¶rt; ¶rt;au nm u , a auauu ma mu au u. aamuam m¶rt; a, ma u mua mu ¶rt;au u ¶rt;aa u uma a; m a mu ¶rt;auu m ¶rt;muam 10% m ¶rt;au, a u nuuau m . 相似文献
4.
Summary The basic formula used in the presented paper gives the relation between the P wave travel-time perturbation and the perturbation of an inhomogeneous transversely isotropic medium, expressed by four perturbations of elastic parameters and by two angles of orientation of the axis of symmetry of transverse isotropy in space. The travel time perturbation is computed along the ray in the unperturbed inhomogeneous isotropic medium. Four elastic parameters and two angles are parametrized in the model under study and a system of equations for many rays is constructed. The equations are linear in the sought elastic parameters and nonlinear in the sought angles, and the iterative Levenberg-Marquardt algorithm is thus used to solve them. The theoretical 3-D inverse problem was solved in the presented numerical example. The data, simulating teleseismic data, were computed in the direct problem and then inverted. The results indicate the applicability and limitation of the presented algorithm in real problems.
a a, unaa n¶rt;aa am, ¶rt;am mu ¶rt; uu u na u uu ¶rt;¶rt; nn umn ¶rt;, a m nuu naamau u ¶rt; au umauu u umuu nn umnuu nmam. u u na um ¶rt; a aa ¶rt;¶rt; umn ¶rt;. nu naam u ¶rt;a a naamuua ¶rt;u u nma uma au ¶rt; u . au u n um nu naama u u n um a umauu umuu, nm un m umamu aum a-aa¶rt;ma ¶rt; u u. am nu¶rt; ¶rt; m u nu. nu muu ¶rt;a aaa a na a¶rt;aa u am ¶rt;a a. mam naam auu u mu nuu nu¶rt;uma a a.相似文献
5.
a mam 10-mu u¶rt;au ¶rt;uauu nmu a anam. auum aam mua ¶rt;uu u nu amu uu, a , muu, u auauu n u mmu u uu umaa u ¶rt; nmu uuau. 相似文献
6.
Václav Petr Jana Pěčová Oldřich Praus Reviewer M. Hvoždara 《Studia Geophysica et Geodaetica》1985,29(2):169-190
Summary Magnetic variations were recorded along three profiles crossing the southeastern margin of the Bohemian Massif. The data were processed in order to get induction vectors (Wiesevectors) and in-phase and out-of-phase induction vectors (Schmucker-vectors). Several events of field variations were separated into external and internal parts. The same events were also treated by a physical-statistical approach. Taking into account these results, we were able to delineate a zone of electrical inhomogeneity. It is in close relation to the Moravo-Silesian lineament. The depth of the internal anomalous field source was estimated at 20 to 25 km.
¶rt;a u uuau n uu n nu, nu — u. u¶rt;uu ( u), n u u n¶rt; u n u¶rt;uu ( ), n ¶rt;u n uau u u u n au ¶rt; uu-uuu ¶rt; u ¶rt;¶rt;u na¶rt; nu -uu . ¶rt; au uu a n a u n¶rt; 20–25 .相似文献
7.
u uuuuaumau uu u m, ¶rt;u a mumau nmu a u nmu mau u nmmu. au n¶rt; nuau ¶rt;mam u u m. nua m¶rt; m u m¶rt;a aau (1960) ¶rt; uu . 相似文献
8.
Josef Bochníček Rezenzenten M. Hvoždara Rezenzenten J. Střeštík 《Studia Geophysica et Geodaetica》1979,23(3):301-303
auam uu ma¶rt;am m¶rt; un ¶rt; nu nm omu mamuu ua. a m n¶rt;aam u aum, m ¶rt; nua a nmuuuam. mm aum ma ¶rt;nam aau maua ua.
Vorgetragen auf dem KAPG-Seminar Geomagnetische Pulsationsindizes, Niemegk//DDR, September 1977. 相似文献
Vorgetragen auf dem KAPG-Seminar Geomagnetische Pulsationsindizes, Niemegk//DDR, September 1977. 相似文献
9.
Summary The present paper deals with theZ-model of the nearly symmetric hydromagnetic dynamo as a generation mechanism of the Earth's magnetic field. TheZ-model of Braginsky [2] was solved for viscous core-mantle coupling [3]. It is shown that a similarZ-model can also be constructed for electromagnetic core-mantle coupling, or for both effects combined. A new part of the azimuthal velocity appears in the equations, but the character of the boundary layer is not changed too much. No numerical solution is presented.
mam auam ma aa Z-¶rt; nmu umuu¶rt;aum ¶rt;ua, ma n¶rt;mam amu au aum n. Z-¶rt; au [2] a a ¶rt; a au¶rt;mu ¶rt; ¶rt; u amu. aam, m n¶rt;a Z-¶rt; m m nma ma ¶rt; a maum au¶rt;mu ¶rt; ¶rt; u amu, uu a ma m uuam. au nm a am auma mu, aam nau m. ua u u nu¶rt;um.相似文献
10.
Summary Simple linear representation of the components of an approximate plane solution of point mass loading of the Earth's surface in a conveniently chosen coordinate system leads to selection of a 2nd-degree curve which is the best fit of the spherical solution for the given Earth model. The new approximate solution, which, analogously to the plane solution, can be called a parabolic solution, enables the simple input parameters of the plane solution to be used also for substantially larger angular distances. The comparison with the spherical solution is carried out by computing the effects of the M2-wave of ocean tides. The results of the computations for the tidal station Brussels prove the two solutions to be in sufficient agreement for global problems as well.
m nu uau aa nuuum nm u m m au nmu u n¶rt;¶rt; um ¶rt;uam ¶rt;m ma u m mnu, ma auu a n¶rt;¶rt;um u u ¶rt; ¶rt;a ¶rt;u u. nuuum u, m n aauu nm u aam naauu u, nm unam nm ¶rt; ¶rt;a nm u ¶rt;a ¶rt; m u amu. au uu u m uu uu 2 u nuu. mam uu ¶rt; nuu mauu ¶rt;aam ¶rt;mum au u u ¶rt;a ¶rt;a a¶rt;a.相似文献
11.
Summary The distribution of radioactive(Th, U, K), major and selected trace(Rb, Sr, Ba, Y, Zr, V, Cr, Ni) elements of granulites from the Saxonian Granulite Complex was studied. Similarly to the South Bohemian granulites, the Saxonian granulites can be divided according to the contents of their major and trace elements into two main groups, groupA containing mostly acid and subacid granulites (K
2
O>2.5%, SiO
2
>68%), and groupB containing mostly intermediate and basic granulites (K
2
O<2.5%, SiO
2
<68%). Statistically significant differences between groupsA andB were found for all major oxides and several trace elements(Rb, V, Cr, Ni). The Saxonian granulites follow the same calc-alkaline trend as the South Bohemian, granulitesA being placed mostly in the rhyolite field and granulitesB mostly in the dacite, andesite and basalt fields of this trend. The investigated granulites are characterized by a considerable scatter ofTh andU contents accompanied by very variableTh/U ratios; theTh andU concentrations of granulitesA are substantially lower than is usual for rocks of corresponding acidity.
¶rt;a an¶rt;u a¶rt;uamu(Th, U, K) u ua ¶rt;u(Rb, Sr, Ba, Y, Zr, V, Cr, Ni) m aum n¶rt;a aaum na. naa, m u¶rt;aum n uu aam n aaum u ¶rt;u am aua, u u uu. aum n u uu ma a¶rt;um ¶rt; ¶rt;nn; nnA nua¶rt;ama a au¶rt; u au¶rt;aum (K 2 O>2,5%, Si O 2 >68%), nnB ¶rt;u u aum (K 2 O<2,5%, SiO 2 <68%). ¶rt; muunnau mm mamumuu m au ¶rt; a u u ¶rt; m ¶rt;u m(Rb, V, Cr, Ni). auaum n¶rt;¶rt;m um- m¶rt; a u -uaum;aumA a¶rt;ma a uum n, uaumB a a ¶rt;aum, a¶rt;um u aam n m m¶rt;a. ¶rt;aum — u unnA — aamum uu ¶rt;au da¶rt;uamu mTh uU.相似文献
12.
Summary The accuracy of wave field extrapolation is studied with respect to the discretization of field data and integral extrapolator. Assuming a far-field approximation of the Rayleigh-Sommerfeld solution for a two-dimensional scalar wave equation, the minimum and the maximum transmitted frequency are expressed as functions of the sampling intervals t, x, and the half-width x0 and angle a of the migration aperture. The theoretical limitation of the transmitted frequency band is tested on numerical examples.
aamuam mm manuu auumu m ¶rt;umuauu n u uma manu nama. ¶rt; u uma u -¶rt;a ¶rt; ¶rt; a au, ¶rt; nuuuu ¶rt;a n mu ¶rt; uua u aua n¶rt;aa amm a uu m a -nmam ¶rt;umuauu t u , nuu 0 u a a uau anm. mu n¶rt;u amm ¶rt;uanaa mmua a u nua.相似文献
13.
Summary A large number of the users of the geomtrical constants of the reference ellipsoid know only the IAG resolutions and not the related special publications; consequently, the numerical values of the derived geometrical constants may be interpreted differently. Some values of possible differences (max. 32 mm) are given, and it is proposed that the GRS-80 geometrical constants be defined by the values of a and f
–1
with unlimited accuracy in the next IAG resolution.
¶rt;a um nam zmuuu nmu n-unu¶rt;a am m uu ¶rt;a¶rt; auauu n z¶rt;uu, a nua nuauu; nm m num a mau u au nu¶rt; zmuu nm. mam nu¶rt;m m au am (a. 32 ) u n¶rt;azam n¶rt; uu n¶rt;m muu nm GRS-80 uuau a, f –1 zau mm.相似文献
14.
15.
Marcela Laštovičková Karel Svoboda Рецензенm A. Janáčková 《Studia Geophysica et Geodaetica》1986,30(2):211-213
au aa ¶rt;a, nuau uuu ma n¶rt; u m muu uu, n¶rt; m¶rt;a nm (). u a m u ¶rt; uuu ma u muuu uuau.
Summary Analysis of the data set describing the chemical composition of the rocks and their electrical parameters was performed by the principal component method. Some relations between chemical composition and electrical parameters were established.相似文献
16.
Miloslav Burda Vincenc Vyskočil Miloš Hübner Reviewer M. Bielik 《Studia Geophysica et Geodaetica》1988,32(1):54-61
Summary Problems of occurrence of density inhomogeneities in the upper mantle are discussed and their gravitational effects in the region of Central Europe are investigated. Attention is namely devoted to the density contrast between the asthenosphere and the lower lithosphere, and its possible dependence on depth.
¶rt;am n nu nmm ¶rt;¶rt;m amuu u uaumau ¶rt;mu a mumuu ¶rt; n. uau ¶rt;m n¶rt; nmm mam ¶rt; am u um u auumu mu aau.相似文献
17.
n¶rt;m mu ¶rt; mu uau aumma. mu aum u mu u m u mu auauu m¶rt;a. u¶rt;m u naam nm nmmuna uau aumma. 相似文献
18.
Summary The linearization approach is used to compute the travel times in inhomogeneous slightly anisotropic media. The basic formulae are outlined and their accuracy demonstrated in comparison with the exact solution based on the zero-order ray theory and the Backus formula (1965). The linearization is extended also to complex media with curved interfaces. The computer program for calculating travel times in 2D, inhomogeneous, slightly anisotropic, complex media is briefly described. The numerical results obtained for a realistic situation and various types of waves are presented to enable the effects of anisotropy and the effects of inhomogeneity on the resulting travel times to be compared.
na uauua n¶rt;¶rt; ¶rt; ama¶rt;aa , anmau aaumn ¶rt;a. ¶rt; u n¶rt; au m u n muu nuuuu u m¶rt; aa (1965). a uauua n¶rt;¶rt; ¶rt; a ¶rt; uuuauau a¶rt;a. am nuaa uuma naa ¶rt; ama¶rt;a ¶rt; ¶rt;. u mam ¶rt; a mun ¶rt;am m um m aumnuu u m ¶rt;¶rt;mu a a anmau .相似文献
19.
aam, m ¶rt;-mau ¶rt;uu a ma au am m¶rt; ma m unmuu m m. ¶rt;a, u a u unmuu annuuam, m am n una u 0,1 u a u ammuuu ¶rt;mau aa m m. 相似文献
20.
Summary The relation between geomagnetic activity and solar activity is studied in long intervals and in individual 11-year cycles, characterized by certain basic parameters, in connection with investigating the prognostic significance of long-term fluctuations of geomagnetic activity [1, 2]. A number of properties as well as sufficiently close relations with a prognostic significance have been found, such as the secular variation of geomagnetic activity, the 22-year cycle of change in the form of the behaviour of geomagnetic activity in 11-year cycles, long-term concurrence of solar and geomagnetic activity and its changes within the 11-year cycle, relations between solar and geomagnetic parameters characterizing the 11-year cycle.
a auu uu u ¶rt; uaum amum ¶rt;u nma u u m¶rt; 11-mu ua am mu ¶rt; ¶rt;m nuauaum amumu.相似文献