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41.
n¶rt; auau uu ¶rt; mnu¶rt; n, n, g, Sg, m anmam anauu ¶rt; numa amu 2.6° ¶rt; 4.7° m aa amu uu (mau). aa, m m auum Sg(D) mam mua ¶rt; m n¶rt;u aum¶rt; uma a uu mu.  相似文献   
42.
A distinct regional dependence of amplitude observations at closely-situated pairs of Central European seismic stations (about 1° apart) was observed for the short-period P waves at teleseismic distances. For the investigated regions, namely Japan, the Kuriles, Kamchatka, the Aleutians, and Alaska, the magnitude corrections change by 0.3 magnitude units. These changes are related to the change of the strike and dip of the sinking lithospheric plates. A relative decrease of the amplitudes, generally observed for different pairs of stations, corresponds to a decrease of the angle between a seismic ray and a slab.  相似文献   
43.
Summary Amplitudes and periods of seismic waves recorded both in the short-period and in the intermediate-period ranges at the seismic stations Prhonice, Praha and Kaperské Hory are influenced by the tectonic situation in the focal regions rather than by the anisotropic structures of the geologic formations underlying the stations. Large amplitude variations and differences in periods due to instrumental effects were also found.  相似文献   
44.
mau x¶rt; u a¶rt;u 8 ¶rt;nu mau ¶rt; uu mu u -ana¶rt; auu naa num mam u u na n, g, Sn u Sg mum ma¶rt;am¶rt;a ¶rt; uu mu. a¶rt;u lam mu aua u umau u mm u a amuu ¶rt; En.  相似文献   
45.
Summary Directionally independent average P residuals computed for waves of teleseismic events arriving under various azimuths and incidence angles provided the basis for estimating the lithosphere thickness beneath the Carpathians and their surroundings. A thin lithosphere (60–80 km) was determined for the Pannonian Basin and the Transylvanian Basin, the thickest lithosphere(about 180 km) beneath the South Carpathians at the contact with the Moesian Platform. In other parts of the Carpathian belt the lithosphere thickens beneath the outer parts towards the SW margin of the East-European and the Moldavian Platforms. The lithosphere thicknesses derived from P residuals correlate well with the magnetotelluric determinations of a layer of increased electrical conductivity in the upper mantle.
Резюме Осре?rt;ненные временные невязкu Р волн, незaвuсuмые оm нanрaвленuя u рaссчumaнные ?rt;ля у?rt;aленных землеmрясенuŭ uз волн, nрuхо?rt;ящuх nо?rt; рaзнымu aзuмуmaмu u у лaмu na?rt;енuя, ?rt;aюm основaнuе ?rt;ля оnре?rt;еленuя мощносmu лumосферы Кaрnam u uх окресmносmеŭ. Тонкaя лumосферa(60–80 км) оnре?rt;еленa ?rt;ля Пaннонско о u Трaнсuльвaнско о бaссеŭнов, a сaмaя мощнaя лumосферa(около 180 км) нaхо?rt;umся nо?rt; Южнымu Кaрnamaмu. В ?rt;ру uх чaсmях Кaрnamско о nоясa мощносmь лumосферы нaрaсmaеm во внешнuх зонaх в нanрaвленuu к ю о-зana?rt;ноŭ окрauне Восmочно-Евроnеŭскоŭ u Мол?rt;aвскоŭ nлamформ. Нaблю?rt;aеmся хорошaя корреляцuя мощносmu лumосферы, оnре?rt;еленноŭ нa основе невязок временu Р волн, с мa нumоmеллурuческuмu ?rt;aннымu nо лубuне слоя nовышенноŭ элекmроnрово?rt;uмосmu в верхнеŭ мaнmuu.
  相似文献   
46.
Summary The large scale anisotropic structures with plunging symmetry axes in the subcrustal lithosphere of central Europe were derived from independent observations of teleseismic P-residual spheres and polarizations of the split SKS waves. The dipping structures are interpreted as remnants of palaeo-subduction systems which retain olivine orientations from ancient oceanic lithosphere. Values of kP and kS estimated from observed teleseismic P and SKS data are within the range of anisotropies found for the upper mantle rocks. The Variscides of central Europe may thus be characterized by two palaeo-subduction systems, with symmetry axes divergent relative to the suture between the Moldanubicum and Saxothuringicum.  相似文献   
47.
We modelled the thickness and seismic anisotropy of the subcrustal lithosphere from the variations of P-wave delay times and the shear-wave splitting observed at seismological observatories and portable stations in the western part of the Bohemian Massif. The Saxothuringian lithosphere is characterized by a total thickness between 90 and 120 km, the Moldanubian lithosphere is generally thicker –120-140 km, on the average. The subcrustal lithosphere of both units is characterised by divergently dipping anisotropic structures and the suture between them is marked by a lithosphere thinning to about 80km. Within the subcrustal lithosphere a complex structure of the transition of both units extends to about 150 km toward the south. We suggest that the Saxothuringian-Moldanubian suture has created a zone of mechanical predisposition for the Tertiary Ohe (Eger) Graben, as well as for the occurrence of earthquake swarms in the region. Most earthquakes occur within the brittle part of the upper crust above the crossing of the suture between the Saxothuringian in the north and the Moldanubian and the Tepl´-Barrandian in the south, with the tectonically active Mariánské Lázn fault.  相似文献   
48.
Three-dimensional general circulation models (GCMs) are 'state-of-the-art' tools for projecting possible changes in climate. Scenarios constructed for the Czech Republic are based on daily outputs of the ECHAM-GCM in the central European region. Essential findings, derived from validating, procedures are summarized and changes in variables between the control and perturbed experiments are examined. The resulting findings have been used in selecting the most proper methods of generating climate change projections for assessing possible hydrological and agricultural impacts of climate change in selected exposure units. The following weather variables have been studied: Daily extreme temperatures, daily mean temperature, daily sum of global solar radiation, and daily precipitation amounts. Due to some discrepancies revealed, the temperature series for changed climate conditions (2×CO 2 ) have been created with the help of temperature differences between the control and perturbed runs, and the precipitation series have been derived from an incremental scenario based on an intercomparison of the GCMs' precipitation performance in the region. Solar radiation simulated by the ECHAM was not available and, therefore, it was generated using regression techniques relating monthly means of daily extreme temperatures and global radiation sums. The scenarios published in the paper consist of monthly means of all temperatures, their standard deviations, and monthly means of solar radiation and precipitation amounts. Daily weather series, the necessary input to impact models, are created (i) by the additive or multiplicative modification of observed weather daily series or (ii) by generating synthetic time series with the help of a weather generator whose parameters have been modified in accord with the suggested climate change scenarios.  相似文献   
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