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211.
Electromagnetic measurements in the vicinity of the KTB drill site. Part II. Magnetotelluric results
Summary In addition to the magnetovariational measurements across an array in Western Bohemia, close to the KTB ultradeep borehole (Germany), discussed in part I of this paper [1], magnetotelluric results from pivot sounding point Ostrvek within the array are presented here. Good quality of long-period magnetotelluric data (period range from 30 s to about 1 hour) allowed structural dimensionality of the medium to be analysed in detail. The geoelectrical structure was identified as a slightly distorted two-dimensional regional substratum, with dominating E - W strike, overlaid by a heterogeneous subsurface layer with extremely strong and anisotropic galvanic distortion effect on the magnetotelluric data. Estimating the total static shift distortion tensor by fitting the local magnetotelluric curve to the curve of the global magnetovariational soundings (for the European continent), the static distortions were identified as of generally multidirectional origin. The resulting telluric ellipse is, however, strongly anisotropic, indicating an approximately SW - NE apparent local strike, which is in the approximate agreement with remote reference magnetovariational results. Finally, the magnetotelluric results from the station Ostrvek are compared with long-period data from the immediate neighbourhood of the KTB borehole on the German territory. 相似文献
212.
Summary A possible relation between the 10-day geomagnetic activity, solar activity and temperatures as measured at the meteorological station Prague - Klementinum in 1932–1975 was sought. It was found that: 1) Kp correlates with the surface temperature in Prague substantially better than Wolf's number R. 2) The correlation between Kp and the surface air temperature is not very close, but is significant at the level p=0.9! 3) If the QBO phase is taken into account, the correlations for the January and February decades of the years 1956–1975 improve as in [27] (van Loon, Labitzke). 相似文献
213.
214.
Bohumil Pícha Václav Červ Josef Pek Reviewer O. Novotný 《Studia Geophysica et Geodaetica》1984,28(1):101-112
um m¶rt;uu n¶rt;¶rt; u ¶rt;uau maum n ¶rt;uma ¶rt;¶rt; ¶rt;a u ¶rt; u uuu ¶rt; u u mumu umauu ¶rt; nu mua-a n¶rt; a¶rt; -ana¶rt; amu mama ¶rt; u au anam um. mua umnmau nm a an¶rt;u mn¶rt;mu mumu aa nuuum n¶rt;umau mm ¶rt;uu ua . 相似文献
215.
Summary Methods of solving the inverse magnetotelluric problem are compared. Basic relations for Newton's method, the least-squares method and Marquardt's method are presented and the convergence properties of these methods are studied. The high effectiveness of Marquardt's method is demonstrated and its application to practical magnetotelluric data is discussed. 相似文献
216.
Libuše Ruprechtová Josef Horálek Reviewer J. Buben 《Studia Geophysica et Geodaetica》1977,21(2):143-147
Summary An attempt was made to verify the possible influence of seismograph characteristics on the first displacement in the P wave. The signals recorded by the broadband seismic channels at Kaperské Hory were treated by a set of pass-band filters, three of them simulating the usual types of seismographs. 相似文献
217.
Prof. Dr. Josef Frechen 《International Journal of Earth Sciences》1981,70(3):1119-1151
Zusammenfassung Regionale Unterschiede der Schichtenabfolge, Schichtausbildung und Xenolithführung zeigen an, da\ die Tuffe der allerödzeitlichen Laacher Bimsdecke an mehreren Stellen gefördert worden sind. Isopachen- und Isoplethendarstellungen und die Xenolithassoziationen ermöglichen es, die Ausbruchsstellen zu lokalisieren. Danach fanden im Laacher See Gebiet wÄhrend des Alleröd in verhÄltnismÄ\ig kurzer Folge Bimsausbrüche statt bei Obermendig, im Meerboden, bei Frauenkirch, zwischen dem Wingertsberg und Thelenberg und im nordöstlichen Teil des Laacher Kessels. Die Ausbruchsstelle im Laacher Kessel ist durch eine ausgedehnte positive geomagnetische Anomalie gekennzeichnet. Die petrographische Zusammensetzung der Basaltauswürflinge in den Laacher See Tuffen gibt Hinweise auf das Alter des Laacher Kessels und auf die Magmendifferentiation in seinem Untergrund.
Regional differences in the sequence and structure of pumice beds, variation of basaltic and sedimentary xenoliths, isopachs and isopleths indicate, that the pumice tuffs of Alleröd age of the Laacher See area were erupted from different places: near Obermendig, in the Meerboden depression, near Frauenkirch, between Wingertsberg and Thelenberg, and in the northern part of the Laacher See basin. The eruption center in the Laacher See basin is marked by a large positive geomagnetic anomaly. Basaltic xenoliths of various composition occurring in the Laacher See pumice tuffs give evidence of an older volcanic phase in the Laacher See basin and of subvolcanic evolution of basaltic magma.
Résumé Les différences régionales dans la séquence stratigraphique, la structure des couches et les variations de leurs xénolithes montrent que les tufs allerödiens du Laacher See proviennent de plusieurs centres d'éruption. Les cartes d'isopaques et d'isoplèthes, ainsi que l'association des différents xénolithes, permettent de localiser ces centres dans la région du Laacher See, près d'Obermendig, dans le Meerboden, à Frauenkirch, entre le Wingertsberg et le Thelenberg et dans la partie nordest du bassin du Laacher See lui-mÊme. Ce dernier lieu est caractérisé par une large anomalie géomagnétique positive. La composition pétrographique des xénolithes basaltiques dans les tufs donne des indications sur l'âge du bassin de Laach et sur les processus de differentiation magmatique dans le soubassement.
, , . . , , , . . .相似文献
218.
Summary In the Part 1 and in a subsequent Part 2 to be published two methods of adjusting a spatial terrestrial network in tri-dimensional space are described. Care has been taken that the nature of the equations used, as well as of the adjustment, correspond to the same in adjustment satellite networks. The adjustment was carried out by the least-squares method according to conditioned observations. Various types of condition equations have been constructed according to the various types of adjusted quantities, and the various alternatives of the introduced errors (changes of input values) and weights. An effort was made to eliminate the ellipsoid of reference to the largest extent. The theory was applied numerically to a model of a smaller network which corresponds in position and height to usual triangulation networks with side lengths of about 30 km.Dedicated to 90th Birthday of Professor Frantiek Fiala 相似文献
219.
Adolf Peretti Jean Dubessy Josef Mullis B. Ronald Frost V. Trommsdorff 《Contributions to Mineralogy and Petrology》1992,112(2-3):329-340
During regional metamorphism of the Malenco serpentinized peridotite (Sondrio, northern Italy), the mineral assemblage pentlandite-awaruite-magnetite-native copper-antigorite-brucite-olivine-diopside is formed. The opaque assemblage indicates very reduced fluids with fO2 values 4 log units below QFM. Primary fluid inclusions were trapped in diopside overgrowth, contemporaneous with the opaque assemblage. These metamorphic fluids are saline aqueous solutions (about 10.4 mol% NaCl equivalent) and contain molecular H2 of approximately 1 mol%, as shown by micro-Raman analysis and microthermometry. The fluids are interpreted to have been formed during deserpentinization at the olivine-in isograd under strong reducing conditions. 相似文献
220.