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91.
Summary On the basis of the 1966–73 data, the effect of the difference between pro- and anti-sectors of the IMF is found to be negligible in the winter midlatitude (Central Europe) ionosphere contrary to the dominant effect of this difference in the high-latitude ionosphere found earlier.
a ¶rt;a a 1966–73. u¶rt;m u m amu ¶rt; pro- u anti- mau . na a u ¶rt;um (¶rt; na) u, , a naa a, naum um u.相似文献
92.
Leonard Guelke 《Geoforum》1985,16(2):131-137
While physical geographers are united in a commitment to the scientific method with its emphasis on quantitative evidence, human geographers face a dilemma in deciding whether to adopt a scientific or humanistic approach in their research. The scientific approach offers a more secure, objective knowledge, but limits the scholar to a relatively narrow range of topics. The humanistic approach allows the scholar to explore a wide range of human experiences, but it lacks rigorous procedures of objective verification. The difficulty of the application of theoretical ideas to human societies can, to some extent, be avoided by adopting an historical approach, with an emphasis on the empirical investigation of human activity as a reflection of ideas. As long as human geographers have a commitment to basing their interpretations of geographical phenomena on objective evidence the possibility of a profitable co-operation exists among proponents of different philosophical approaches. A unified human geography embracing scholars of diverse views depends for its success on the identification of geographical problems that transcend philosophical and theoretical points of view. 相似文献
93.
94.
Summary The hypothesis of an expanding Earth is discussed on the basis of lunar laser ranging It is provcd that the given data do not indicate a secular increase in the principal moment of the Earth's inertia which would have to occur if the Earth were really expanding.
¶rt;amunma au u mu u ammuu a¶rt;u u ¶rt;a n a auu . aam, m n mu ¶rt;a m umamu amaua ma uuu u, m ¶rt; nmmam auu, u n¶rt; u m.相似文献
95.
Libuše Ruprechtová Klára Mrázová Jaroslav Fiedler Reviewer A. Zátopek 《Studia Geophysica et Geodaetica》1984,28(3):286-293
Summary The calculation procedures for determining epicentre parameters of weak near shocks with foci in Poland are discussed and tested for explosions with known epicentres.
m m¶rt; ¶rt; n¶rt;u num a uu m num nmua n auauu, u mu a mumuu u, n muu ¶rt;au uu mau. au mam nam (a. 4) nu nuuu na 71 u m ¶rt;u n¶rt; ¶rt; a auu ¶rt;a [11].相似文献
96.
Jana Konopásková Vlastislav Červený Reviewer I. Pšenčik 《Studia Geophysica et Geodaetica》1984,28(2):113-128
ma ama m n¶rt;u am[1]. u ama, m¶rt;au n unm ¶rt; uuauu ma m nau a¶rt;a. a uau ¶rt;m ma a muna . au mu mamau n [1], m m¶rt;au n ¶rt;am ¶rt;mam m mam ¶rt;a u amu aa mu. aumu amu, uauau n ma nuu ¶rt;a . m am ¶rt;am mumm mam a naama am, aa uu L
0
au n. aa, m am mam namuu aum m L
0
. amu aa mu u aumu amu, a m mam n ¶rt; u L
0
. u uu L
0
, anum¶rt; ma amu aa mu nuam, nu aua nam m, m uu L
0
auum. aumu amu, u L
0
um m uau m a uuu anum¶rt; u, mmmu a. uu L
0
, uuu nam. ma uam mumm mam ¶rt;a ¶rt;u naama am. uau ¶rt;m ma anum¶rt; u ma muna S, S u SS. 相似文献
97.
¶rt;au uu aum nuuumu u aumnuu ¶rt; aa aam n¶rt; am amuu u namuu ¶rt;au. amu uu aumnuu nuuumu, a amu ¶rt;au, m ¶rt;mu au ma nma aaumu m¶rt; ¶rt;a, m a amu uu aum m mnu n¶rt;u ¶rt; mm uaum amua n¶rt; ¶rt;au. u aumnuu nu a namu ¶rt;auu(<1%) a uuu m nuuumu i uaum amua. u aumnuu ¶rt;mu uu uum aauuau ¶rt;ua am m uu, m, m ¶rt; u au namu ¶rt;auu. 相似文献
98.
99.
Leonard Robert Gardner 《Chemical Geology》1984,46(1):55-73
Stable carbon and oxygen isotope measurements have been obtained from ten calcareous soil profiles developed on noncalcareous parent materials in Nevada and New Mexico. Despite the number of variables that can affect the isotopic composition of soil carbonate, most of these profiles show remarkably little variation in δ 13C and δ 18O with depth. This tendency towards uniformity is attributed to the fact that pedogenic carbonate forms by the incremental accumulation of a large number of small aliquots of CaCO3. As the number of aliquots of CaCO3 increases, the composition of their sum, which is the calcareous horizon itself, tends to converge to the long-term average of the individual aliquots. A mathematical model is presented to show how the time required for convergence is affected by the amplitude and period of aliquot variation and the extent of dissolution and reprecipitation of previously deposited carbonate. Calculations further indicate that in some cases the variation in δ 18O of soil carbonates may be moderated by the opposing effects of temperature change on the H2OCaCO3 fractionation factor and on the extent of evapotranspiration.The data of this study indicate that soil carbonates from sites within a homogeneous climatic region show relatively little site-to-site variation in δ 18O as compared to geographical variation in δ 13C. This suggests that the δ 18O of soil carbonates is primarily controlled by broad climatic factors (rainfall composition and temperature) whereas site factors (e.g., soil CO2) have a strong effect on δ 13C. In Nevada and New Mexico the δ 18O of Pleistocene calcareous profiles is 2.0–4.0‰ lighter than that of nearby Holocene soil carbonate, suggesting that old well-developed profiles may have formed dominantly under cooler pluvial conditions. 相似文献
100.
The orthogneiss bodies of the Moldanubicum in the western part of the Bohemian-Moravian Heights (eskomoravská vrchovina) are apoleucogranites, presumably of Precambrian age and probably of anatectic origin. Most orthogneiss bodies have been shown to contain greisens transformed by regional metamorphism. The greisens have maintained their identity during regional metamorphism below higher almandine-amphibolite facies grade, i.e. over the stability field of muscovite. Massive quartz (metamorphosed vein quartz) is frequent, and mineralization is associated with it in a few localities. Greisens in orthogneisses may serve as evidence of magmatic origin. 相似文献