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41.
An updated list of earthquakes and earthquake parameters (location, homogenized magnitude, macroseismic data) for the southern Baltic Sea area reveals activity north of the sea, whereas there are very few epicentres in the sea itself and in the region south of it. This is the first study to combine seismological data for the whole region to cover also the sea. Macroseismic data for the 1930 earthquake were reinvestigated leading to an intensity of V–VI (MM or MSK scale), a radius of perceptibility of 135 km and an unusually big focal depth of about 40 km. It is difficult to correlate individual earthquakes with specific faults, but some seismotectonic relations are suggested, e.g. for the Tornquist zone, the predominant structure of the region. Only few reliable focal-mechanism solutions exist. Possible seismogenic processes (ridge push, isostasy, etc) are discussed.  相似文献   
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The short wavelength geoid undulations, caused by topography, amount to several decimeters in mountainous areas. Up to now these effects are computed by means of digital terrain models in a grid of 100–500m. However, for many countries these data are not yet available or their collection is too expensive. This problem can be overcome by considering the special behaviour of the gravity potential along mountain slopes. It is shown that 90 per cent of the topographic effects are represented by a simple summation formula, based on the average height differences and distances between valleys and ridges along the geoid profiles, δN=[30.H.D.+16.(H−H′).D] in mm/km, (error<10%), whereH, H′, D are estimated in a map to the nearest 0.2km. The formula is valid for asymmetric sides of valleys (H, H′) and can easily be corrected for special shapes. It can be used for topographic refinement of low resolution geoids and for astrogeodetic projects. The “slope method” was tested in two alpine areas (heights up to 3800m, astrogeodetic deflection points every 170km 2) and resulted in a geoid accuracy of ±3cm. In first order triangulation networks (astro points every 1000km 2) or for gravimetric deflections the accuracy is about 10cm per 30km. Since a map scale of 1∶500.000 is sufficient, the method is suitable for developing countries, too.  相似文献   
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Zusammenfassung Während des Oberkarbons befand sich das Rheinische Schiefergebirge im Endstadium der Faltung und im Aufstieg. Zur gleichen Zeit entwickelte sich im Saarland ein intramontanes Becken, das die Schuttmassen des aufsteigenden Gebirges aufnahm. Es kam zur Ablagerung von limnischen Sedimenten in dem flachen Saar-Nahe-Becken. Die paläomorphologische Gestaltung des Gebietes ist aus dem Faziesbild der Sedimente ablesbar.
During the Upper Carboniferous the Rheinisches Schiefergebirge was in the final stage of folding and in the act of uplift. At the same time an intrageosyncline developed in the Saarland, which took up the detritus of the uplifting Northern mountains. Limnic sediments deposited in the flat Saar-Nahe-Basin. The paleomorphological development of the region can be recognized.

Résumé Pendant le Carbonifère supérieur le massif schisteux rhénan se trouvait dans la phase finale de plissement et de surrection. En même temps se formait une dépression interne recevant les masses d'érosion de la montagne bordiére septentrionale. Des sédiments limniques se déposaient dans la dépression peu profonde de la Sarre-Nahe. Les faciès des sédiments nous montrent la topographie paléomorphologique du territoire.

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Wir danken der Deutschen Forschungsgemeinschaft für die Förderung der Untersuchungen.  相似文献   
46.
The catalogue by Grünthal et al. (J Seismol 13:517?C541, 2009a) of earthquakes in central, northern, and north-western Europe with M w????3.5 (CENEC) has been expanded to cover also southern Europe and the Mediterranean area. It has also been extended in time (1000?C2006). Due to the strongly increased seismicity in the new area, the threshold for events south of the latitude 44°N has here been set at M w????4.0, keeping the lower threshold in the northern catalogue part. This part has been updated with data from new and revised national and regional catalogues. The new Euro-Mediterranean Earthquake Catalogue (EMEC) is based on data from some 80 domestic catalogues and data files and over 100 special studies. Available original M w and M 0 data have been introduced. The analysis largely followed the lines of the Grünthal et al. (J Seismol 13:517?C541, 2009a) study, i.e., fake and duplicate events were identified and removed, polygons were specified within each of which one or more of the catalogues or data files have validity, and existing magnitudes and intensities were converted to M w. Algorithms to compute M w are based on relations provided locally, or more commonly on those derived by Grünthal et al. (J Seismol 13:517?C541, 2009a) or in the present study. The homogeneity of EMEC with respect to M w for the different constituents was investigated and improved where feasible. EMEC contains entries of some 45,000 earthquakes. For each event, the date, time, location (including focal depth if available), intensity I 0 (if given in the original catalogue), magnitude M w (with uncertainty when given), and source (catalogue or special study) are presented. Besides the main EMEC catalogue, large events before year 1000 in the SE part of the investigated area and fake events, respectively, are given in separate lists.  相似文献   
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Large data sets covering large areas and time spans and composed of many different independent sources raise the question of the obtained degree of harmonization. The present study is an analysis of the harmonization with respect to the moment magnitude M w within the earthquake catalogue for central, northern, and northwestern Europe (CENEC). The CENEC earthquake catalogue (Grünthal et al., J Seismol, 2009) contains parameters for over 8,000 events in the time period 1000–2004 with magnitude M w ≥ 3.5. Only about 2% of the data used for CENEC have original M w magnitudes derived directly from digital data. Some of the local catalogues and data files providing data give M w, but calculated by the respective agency from other magnitude measures or intensity. About 60% of the local data give strength measures other than M w, and these have to be transformed by us using available formulae or new regressions based on original M w data. Although all events are thus unified to M w magnitude, inhomogeneity in the M w obtained from over 40 local catalogues and data files and 50 special studies is inevitable. Two different approaches have been followed to investigate the compatibility of the different M w sets throughout CENEC. The first harmonization check is performed using M w from moment tensor solutions from SMTS and Pondrelli et al. (Phys Earth Planet Inter 130:71–101, 2002; Phys Earth Planet Inter 164:90–112, 2007). The method to derive the SMTS is described, e.g., by Braunmiller et al. (Tectonophysics 356:5–22, 2002) and Bernardi et al. (Geophys J Int 157:703–716, 2004), and the data are available in greater extent since 1997. One check is made against the M w given in national catalogues and another against the M w derived by applying different empirical relations developed for CENEC. The second harmonization check concerns the vast majority of data in CENEC related to earthquakes prior to 1997 or where no moment tensor based M w exists. In this case, an empirical relation for the M w dependence on epicentral intensity (I 0) and focal depth (h) was derived for 41 master events, i.e., earthquakes, located all over central Europe, with high-quality data. To include also the data lacking h, the corresponding depth-independent relation for these 41 events was also derived. These equations are compared with the different sets of data from which CENEC has been composed, and the goodness of fit is demonstrated for each set. The vast majority of the events are very well or reasonably consistent with the respective relation so that the data can be said to be harmonized with respect to M w, but there are exceptions, which are discussed in detail.  相似文献   
49.
The comparison of macroseismic intensity scales   总被引:5,自引:1,他引:4  
The number of different macroseismic scales that have been used to express earthquake shaking in the course of the last 200 years is not known; it may reach three figures. The number of important scales that have been widely adopted is much smaller, perhaps about eight, not counting minor variants. Where data sets exist that are expressed in different scales, it is often necessary to establish some sort of equivalence between them, although best practice would be to reassign intensity values rather than convert them. This is particularly true because difference between workers in assigning intensity is often greater than differences between the scales themselves, particularly in cases where one scale may not be very well defined. The extent to which a scale guides the user to arrive at a correct assessment of the intensity is a measure of the quality of the scale. There are a number of reasons why one should prefer one scale to another for routine use, and some of these tend in different directions. If a scale has many tests (diagnostics) for each degree, it is more likely that the scale can be applied in any case that comes to hand, but if the diagnostics are so numerous that they include ones that do not accurately indicate any one intensity level, then the use of the scale will tend to produce false values. The purpose of this paper is chiefly to discuss in a general way the principles involved in the analysis of intensity scales. Conversions from different scales to the European Macroseismic Scale are discussed.  相似文献   
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The paper describes the European System for Particle and AstrophysicalCyber Education (ESPACE). After a general introduction to the projectand its ideas the contents of the multimedia teaching and learning systemare presented. It is followed by a discussion about the didactical aspectsof modern multimedia technology related to the project. Finally themultimedia and programming structures are explained and futureperspectives are given.  相似文献   
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