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1.
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
2.
3.
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
4.
50 au mn nma a mumuu auu, m ¶rt; aul mmuu uma, a¶rt;au n mu u¶rt;a u uua aauu u mmu. mam naam, m amu mn nma mmmm mu¶rt;a, u a au : 相似文献
5.
Summary A non-linear model of trochoidal waves is presented which represents a geometrical and kinematical generalization of Gerstner's waves and of the results of[2–4].
¶rt;aam ¶rt; mu¶rt;a , ma m u ma u am[2–4] mu umuu u uamu mm ¶rt;u.相似文献
6.
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
7.
Theodor Stocks 《Ocean Dynamics》1949,2(6):295-298
Summary Echo soundings of the U.S. Cruiser Milwaukee in the Puerto Rico Trough in 1939 are briefly discussed, and two depths of 30246 feet or 9219 m, found at 19° 36 N, 68° 20.5 W and at 19° 35N, 68° 8.75W, are stated to be the greatest depths which are known so far in the Atlantic Ocean. 相似文献
8.
nma nu SS u nmau u nau a¶rt;a ¶rt;u nma u u a au 11-mu ua. u ¶rt; nm ¶rt; n. a¶rt;am nuu nu SS u. 相似文献
9.
Summary The effect of the IMF sector boundary crossing (IMF SBC) in the vorticity area index (VAI) — the well-known dip in the VAI after IMF SBC — is found to be independent of the IMF SBC effect in the cosmic ray flux. This finding refutes a recent suggestion by Lundstedt [1] that the IMF SBC effect in VAI is caused by a decrease in cosmic ray flux, but supports the concept of the IMF SBC effects in the ionosphere and atmosphere developed by Latovika [2–4]. Cosmic rays seem to affect the troposphere in another way.
¶rt;mu nu mau nam aum n ( ) a u¶rt; na¶rt;u aumu () — um uu n — a¶rt; auu m ma nm uu . mm mam nam ¶rt;a n¶rt;u ¶rt;m¶rt;a [1], m m a nuu nma uu , n¶rt;¶rt;uam nu m u u am, aum amu [2–4]. am m uu u m um a mn ¶rt;u a.相似文献
10.
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
11.
Summary By using a general model of optimum elimination of systematic effects[5], the procedure has been developed for the optimum processing of gravimetric observations affected by the drift in a one-stage net, and statistically justified characteristics of the accuracy of the points of this net have been determined.
u uuu u ¶rt;u nmua uuauu um amuu uu [5] aamaa m¶rt;ua nmua amuaumuu uu ¶rt; aa ¶rt;-man mu; nu¶rt; mamumuu aamumuu mmu m¶rt; m m mu.相似文献
12.
Jaromír Janský Jan Zedník Vít Kárník Reviewer J. Vaněk 《Studia Geophysica et Geodaetica》1988,32(3):264-271
Summary The theoretical medium period PV-magnitude calibrating curves were computed for the Earth model PREM and a wide range of focal depths. The calculated set of curves reflects the distribution of model parameters, the influence of source radiation was not taken into account. The widely used Gutenberg's empirical calibrating curves were compared with the theoretical ones. Pronounced deviations in the shape and differences in the level of isolines were found. Thus, if model PREM is considered to be representative of the Earth's structure, the empirical calibrating curves (D, h) for magnitude determination currently used in seismological practice, have to be verified.
auma mmuu au u u ¶rt; n¶rt;u aum¶rt; - n ¶rt;nu¶rt; annaam ¶rt; ¶rt;u u RE u ¶rt;uanau aa. uu maam an¶rt;u naam ¶rt;u ma uu u umua. u nu nuuu au u ma u a mmuuu uu. u a¶rt; mu auu n u u. au a, u num ¶rt; RE n¶rt;maum ¶rt; mu u, m ¶rt;u num nuuu au u (D, h) ¶rt; n¶rt;u aum¶rt;, m am unm u namu.相似文献
13.
aamuam mam uu mn nma ma-au a. a¶rt; uua¶rt;uma mnam, uuma mnn¶rt;mu u mn nma m ¶rt;uamau au uu uma, n¶rt; m n¶rt; mn nm nu¶rt; a. 2. a u au Q=1,99 u 2,06×10–6 /2 am ¶rt;au mu n ua amu, ma mu (2,5×10–6 a/2 ) aum nam mm ¶rt;uana. um mm am na m¶rt;, ¶rt;¶rt; nu¶rt;m am mam. 相似文献
14.
nua u mam n ma aa ¶rt;mn ¶rt;u aa, ma a n¶rt;a [1]. mma m ¶rt;u aa a ¶rt;auu nauMi (uuuu n) uMa (¶rt;uauu anm), m amm u nu [2–5]. u¶rt;m mam u nu ¶rt;u ¶rt; u¶rt; mu ¶rt; u a ¶rt; ¶rt;a. mu a aa, n¶rt;ua m a aa, nua a¶rt; u u i uu a a¶rt; zi nu nu aa ¶rt; ¶rt;a, m ¶rt;um mua m, a¶rt;u ¶rt; a, ¶rt;m, mnam, anu ¶rt; naa, nm a an u nu. a ¶rt;mn ¶rt;u m n a nu u ¶rt;mn ¶rt;u, ma a ma n¶rt;a [1]. 相似文献
15.
nua naam u nuu amamuu un uu mau an () u (), umua nu ¶rt; ¶rt;a¶rt; nu 7 u aua ¶rt;a¶rt; m¶rt;um aa naa u . a ¶rt;a nu amua ¶rt;m un ¶rt; u¶rt;au mmu am aua u a au uu uu mu. 相似文献
16.
Summary The relation of short period PKP1 and PKP2 amplitudes from deep earthquakes in the Tonga region observed at a seismological station in Central Europe, is compared with the theoretical relations computed for different source radiation parameters and depths. The Preliminary Earth Model was used in the computations. Qualitatively good agreement of observed and calculated values was found for the radiation pattern corresponding to the likely geometry of the Tonga subduction zone. The influence of the variation of some source and model parameters on the calculated PKP1 and PKP2 relation is discussed.
¶rt;a au mu anum¶rt; mnu¶rt; PKP1 u PKP2 mu mu a, anua ¶rt; u mau ma n, mmmuu mmuuu uuau, aumau ¶rt; a naam ua umua uu aa. ama unaa ¶rt; PREM. a¶rt; u auma uu ¶rt;am am au ¶rt; a uu, mmm mmuu ¶rt;uu a a. ¶rt;am uu auau naam umu u ¶rt;u a uu am mu anum¶rt; PKP1 u PKP2.相似文献
17.
Martin Šamaj Reviewer J. Horák Reviewer Z. Jaňour 《Studia Geophysica et Geodaetica》1982,26(2):187-192
ama mam maum n¶rt; n¶rt;um ma u ¶rt;, ¶rt;u ¶rt;unu nu nu au muu u. ¶rt;aa ¶rt; aa a uu au mm ¶rt;uuu n m¶rt;a am. u ¶rt;a n¶rt;aam m ¶rt; muu m nau am u u a um anu u m umu au, m ¶rt;aa ¶rt; a nm n¶rt;um nmam an¶rt;u mauu nu . 相似文献
18.
Alexander P. Anufriev Ivan Cupal Reviewer G. Siráň 《Studia Geophysica et Geodaetica》1987,31(1):37-42
Summary The behaviour of the poloidal and toroidal magnetic field at the core-mantle boundary is analysed in more detail, assuming that the conductive layer in the lowest mantle is thin. We can conclude that, in the case of the Z-model of the nearly symmetric hydromagnetic dynamo, the poloidal field may be considered potential everywhere in the mantle and that the azimuthal field depends on the geostrophic azimuthal velocity in the same manner as derived in[1] and[3].
aau ¶rt;-amu n¶rt;nuu m n¶rt; amuu aauum n¶rt;u nu¶rt;a u mu¶rt;a n. am ¶rt;, m Z-¶rt;u nmu umuu¶rt;aum ¶rt;ua aum nu¶rt;a n umam nmua ¶rt; amuu a n¶rt;u . ¶rt;m¶rt;am na [1] u [3] auum auma aum n m auma mu.相似文献
19.
Karel Diviš Vladimír Tobyáš Bohumil Chán Reviewer Z. Šimon 《Studia Geophysica et Geodaetica》1989,33(2):206-209
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.相似文献
20.
Summary Based on model considerations it is shown that, under certain assumptions, upper cyclogenesis may be expected in the region of the auroral oval as a result of heat released at the time energetic particles of extraterrestrial origin penetrate into the lower stratosphere or even troposphere.
a auu ¶rt; a¶rt;u naa, m nu m n¶rt;nu u¶rt;am u amu aa aa mam ¶rt;u mna nuu muu amu nu¶rt;u u mam uu mn.相似文献