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1.
u¶rt; am ¶rt; mua maum aa nu ¶rt;uu ma n¶rt;a mnu ma auau am. a¶rt;¶rt;a mu m¶rt; auu a¶rt;am n¶rt;um m nm aa u n uu naua nu¶rt;a ma uuaama aumam ma nm aa u uu uuma u. 相似文献
2.
Summary We search for the effects of the interplanetary magnetic field (IMF) sector boundary crossing (SBC) in upper stratospheric ozone. The SBUV data (Nimbus-7) at the 10, 3 and 1 hPa levels are analysed for latitudes 45° N and 55° N for winters of the period December 1979 to December 1982. An effect of the IMF SBC wos only found at the 10 hPa level. These first results concerning the IMF SBC effect in upper stratospheric ozone are rather preliminary.
¶rt;m uu nu mau () nam aum n () a mam. SBUV ¶rt;a (u-7) a nm ¶rt;au 10, 3 u 1a aauum ¶rt; um 45° u 55° . . ua nu¶rt;a ¶rt;a 1979 – ¶rt;a 1982. m uu a¶rt; m a 10a. mu n mam n uuu a mam m n¶rt;aumu.相似文献
3.
am ¶rt; mau mu ma uaumau u m a ma, ua aam ¶rt;uu ¶rt;a ma. a ma aamuam u¶rt;; n¶rt;aam u, m uaumau n nua mu nmu ¶rt; ¶rt;mam u mn, u m uma aua umuoa u nu u unu¶rt; uuu. u¶rt;um amo u, ¶rt;a ¶rt;a ¶rt;o 4- n¶rt;a um. 相似文献
4.
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
5.
The gravitational field of topographic-isostatic masses and the hypothesis of mass condensation 总被引：2，自引：0，他引：2
The topographic masses (TM) load the interfaces within the earth; namely TMs are compensated by an isostatic adjustment which might depend on time. Here we focus on the loading gravitational potential to which we refer as the topographic potential. We aim at a rigorous integral representation for the topographic potential of gravity which results in corollary one and two.In addition, a rigorous computation of the gravitational potential of a massive non-spherical shell is achieved which is limited by shape functions which represent the earth's topography (heights) and the negative topography (depths) which substitutes the internal surface of isostatic compensation. Finally by the third corollary the single layer potential is given of those masses which are condensed onto a reference sphere, the basis for the standard loading potential. The hypothesis of mass condensation is confronted with the exact representation, namely in the external distant zone, the near zone and the internal distant zone. 相似文献
6.
A. Gouda Hussain 《Pure and Applied Geophysics》1987,125(1):67-90
The palaeo-intensities (F
a) of the geomagnetic field in Egypt at some ages are determined by archaeomagnetic measurements and found to be:F
a=36.2 T at 3100 B.C., Fa=46.8 T at 3000 B.C.,F
a=36.5 T at 2780 B.C., 49.0 T at 2500 B.C., 36.4 T at 2200 B.C., 57.5 T at 1990 B.C., 62.1 T atca 1400 B.C., 61.5 T at 1400 B.C., 69.9 T at 600 B.C., 59.3 T at 550 B.C., 79.9 T at 460 B.C., 73.7 T at 450 B.C., 69.7 T at 320 B.C., 56.2 T at A.D. 50, 64.9 T, at A.D. 400, 54.4 T at A.D. 300, 57.5 T at A.D. 700 and 43.0 T at A.D. 1975.The palaeo-inclinations (I
a) at some ages are found to be:I
a=24.2° at 420 B.C., 44° at A.D. 50, 60.7° at A.D. 703 and 42° at A.D. 1795.The measured values ofF
a are affected by the anisotropy of magnetic susceptibility of the samples by 13% to 20% of the expected correct value. The suitable correction of this effect is by multiplyingF
by 1/((1+0.2(/90)) andF
by 1/((1–0.13 (/90)), whereF
andF
are the resultant values ofF
a if the laboratory field is perpendicular or parallel to the wall of the sample during the Thelliers' experiments, respectively, and is the angle between the direction of natural remnant magnetization of the sample and the direction of the laboratory field.The results of this paper, together with the previous results for Egypt and the neighbourhoods, lead to the production of the secular variation curve of the geomagnetic field in Egypt for the last 5000 years. The intensity of the field shows a periodicity of about 400 years with multiples. 相似文献
7.
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
8.
Summary Relations for the direct transformation of the Cartesian coordinate system into a system of geodetic coordinates.
u ¶rt;u , , z ¶rt;uu , , h.相似文献
9.
Summary The paper deals with a comparison of two models used in determining the heat flow qM at the lower boundary of two-dimensional geothermal models of the Earth's crust. Method I is based on a linear relationship between the component of the surface heat flow, which is not generated by heat sources inside the model, and the heat flow qM. This method uses a regularization process, in which the variation of the sought function qM is limited from above. Method II is the most frequently used iterative method, in which the (i + 1)-th approximation of qM is determined from the surface heat flow, corresponding to the i-th approximation of qM used as a boundary condition in solving the direct problem. The comparison of both methods has revealed that the solution obtained by method I satisfies the supposed reality better than the solution obtained by method II. Method II is attractive especially for its simplicity. To eliminate the local variations of the estimated heat flow qM, which are due to automatic transmission from the surface heat flow, a combination of method II with some smoothing procedure could be applied.
¶rt;am ¶rt;a m¶rt;a uu mn nma qM a uau ¶rt; muu ¶rt; . m¶rt; unm u ¶rt; ma nm nma, ma uaa umuau mna mu ¶rt;u, u nm qM. m m¶rt; nu n uauu, auuau auau u uu qM . m m¶rt;, mu nm ¶rt; u n a , umau: (i + 1)-a annuau nma qM um n auma nm nma, ma i- annuauu qM. au ¶rt;m, m nm qM, a¶rt; n m¶rt;, mam n¶rt;naa ¶rt;mummu , u, n m m¶rt;. m m¶rt; nuam nmm. ¶rt; mau a auau a¶rt; nma qM, uu ¶rt;mu amamu na u auau nm nma, ¶rt;a uuam au-u¶rt; m¶rt; auau.相似文献
10.
Summary The regular astronomical determinations of the geographic latitude and UT from Ondejov PZT observations were used to estimate the fluctuations with a frequency of 1.00217 of the sidereal day, corresponding to the theoretical value of the frequency of the nearly diurnal free wobble of the pole. The combined polar wobble and nutation as reflected in astronomical observations was analysed, and a method of estimating the amplitudes of the periodic components, based on observing changes of latitude and time during the separate observation nights, is proposed. The numerical solution indicates that fluctuations which can be considered a manifestation of retrograde free nutation with an amplitude of approximately 0.02, are present in the PZT observations.
uuau um u u u ¶rt; una ¶rt; u au amm 1,002 17 ¶rt; m, mmm ¶rt; um ¶rt;uu na, ¶rt;am aau uu ¶rt;u mauu u ¶rt;uu na amuu a¶rt;u. ¶rt;aam m¶rt; ¶rt; u nu¶rt;uu ua, u¶rt;u u uu um u u m¶rt; a¶rt;u. u mam u¶rt;um a ¶rt; um mauu anau nmu ¶rt;uu a mu anum¶rt; 0,02.相似文献
11.
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;.相似文献
12.
Summary An explicit solution is obtained for the system of equations describing the spheroidal motion in a homogeneous, isotropic, gravitating, elastic medium possessing spherical symmetry. This solution is used to derive the Green's dyad for a homogeneous gravitating sphere. The Green's dyad is then employed to obtain the displacement field induced by tangential and tensile dislocations of arbitrary orientation and depth within the sphere.Notation
G
Gravitational constant
-
a
Radius of the earth
-
A
o
=4/3 G
-
Perturbation of the gravitational potential
-
Circular frequency
-
V
p
,V
s
Compressional and shear wave velocities
-
k
p
=/V
p
-
k
s
=/V
s
-
k
p
[(2.8)]
- ,
[(2.17)]
-
f
l
+
Spherical Bessel function of the first kind
-
f
l
–
Spherical Hankel function of the second kind
-
x
=r
-
y
=r
-
x
o
=r
o
-
y
o
=ro
-
x
=r k
s
-
y
=r k
p
-
x
o
=r
o
k
s
-
y
o
=r
o
k
p
-
=a
-
=a
-
[(5.17)]
-
m, l
相似文献
13.
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
14.
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
15.
Summary The ionospheric effects of the interplanetary magnetic field (IMF) sector boundary crossings are studied for the winters of 1963–69. They are considerably stronger for proton than for non-proton sector boundaries. There are two different types of effects. The geomagnetic type is a disturbance, observed in geomagnetic activity, the night-time ionosphere and the day-time F2 region near the geomagnetic equator. The effect in the ionosphere is interpreted in terms of the IMF sector boundary crossing related changes in geomagnetic activity. The tropospheric type is aquietening, observed in tropospheric vorticity and in the day-time mid-and low-latitude ionosphere (except the geomagnetic equator region). The mechanism of this effect remains unexplained.
¶rt;m u m nu mau nam aum n () ¶rt; u 1963–69. u m u ¶rt; nm ¶rt; a mau. mm ¶rt;a m¶rt; muna m. aum m u, a¶rt;a aum amumu, u u ¶rt; F2 amu uuaum ama. mu u m ¶rt;mu uu aum amumu, m a nu mau . n mun m nu, a¶rt; aumu mn u ¶rt; ¶rt;- u uum u (a uu amuaum ama). au m ma um.相似文献
16.
au u¶rt;um u mu ¶rt; umu u amu, aa aum, u nuu anmuaum n mu , a ma u n¶rt;nu, m amau uu aum mu u(
a a) nnua nu u nam nmama aum mu, aa naam uu . au mmuu mu u a auu ¶rt;a aaua a ¶rt;am a mum uumuu naam ¶rt;a na u ama, n¶rt; a¶rt; uu nu aua ¶rt;nuuaum n mu u. mu ¶rt; num uu, a mmmuu namu naamau , ¶rt; m¶rt; u aua nuu anmuaum n, auam mn uu, a m naama . 相似文献
17.
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
18.
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
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 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