全文获取类型
收费全文 | 108篇 |
免费 | 5篇 |
专业分类
测绘学 | 2篇 |
大气科学 | 27篇 |
地球物理 | 29篇 |
地质学 | 42篇 |
海洋学 | 4篇 |
天文学 | 2篇 |
自然地理 | 7篇 |
出版年
2024年 | 2篇 |
2023年 | 3篇 |
2022年 | 1篇 |
2021年 | 3篇 |
2020年 | 1篇 |
2019年 | 2篇 |
2018年 | 4篇 |
2017年 | 5篇 |
2016年 | 11篇 |
2015年 | 3篇 |
2014年 | 5篇 |
2013年 | 6篇 |
2012年 | 7篇 |
2011年 | 2篇 |
2010年 | 2篇 |
2009年 | 1篇 |
2008年 | 4篇 |
2007年 | 1篇 |
2006年 | 6篇 |
2005年 | 6篇 |
2004年 | 4篇 |
2003年 | 2篇 |
2002年 | 6篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1970年 | 1篇 |
1966年 | 2篇 |
1961年 | 1篇 |
1959年 | 2篇 |
1954年 | 1篇 |
1952年 | 2篇 |
排序方式: 共有113条查询结果,搜索用时 15 毫秒
1.
Christof Müller Bernd Milkereit Thomas Bohlen Friedrich Theilen 《Geophysical Prospecting》2002,50(5):517-526
The use of Boomer sources for 3D seismic imaging of shallow marine structures was investigated in a feasibility study. Boomers show sufficient stability to be used in multichannel seismic surveys. The acquisition of a high-frequency, densely sampled seismic data volume was successfully performed in the Baltic Sea. A Pleistocene fluvial channel system and shallow gas accumulations were revealed beneath the unconsolidated sediments which constitute the sea-floor in the southern Kiel Bay. 相似文献
2.
The Permocarboniferous basins in Northeast Germany formed on the heterogeneous and eroded parts of the Variscan orogene and its deformed northern foreland. Transtensional tectonic movements and thermal re-equilibration lead to medium-scale crustal fragmentation, fast subsidence rates and regional emplacement of large amounts of mostly acidic volcanics. The later basin formation and differentiation was triggered by reversals of the large-scale stress field and reactivation of prominent zones of weakness like the Elbe Fault System and the Rhenohercynian/Saxothuringian boundary that separate different Variscan basement domains in the area. The geomechanical behaviour of the latter plays an important role for the geodynamic evolution of the medium to large-scale structural units, which we can observe today in three dimensions on structural maps, geophysical recordings and digital models. This study concentrates on an area that comprises the southern Northeast German Basin, the Saale Basin, the Flechtingen High, the Harz Mountains High and the Subhercynian Basin. The presented data include re-evaluations of special geological and structural maps, the most recent interpretation of the DEKORP BASIN 9601 seismic profile and observations of exposed rock sections in Northeast Germany. On the basis of different structural inventories and different basement properties, we distinguish two structural units to the south and one structural unit to the north of the Elbe Fault System. For each unit, we propose a geomechanical model of basin formation and basin inversion, and show that the Rhenohercynian Fold and Thrust Belt domain is deformed in a thin-skinned manner, while the Mid-German Crystalline Rise Domain, which is the western part of the Saxothuringian Zone, rather shows a thick-skinned deformation pattern. The geomechanical model for the unit north to the Elbe Fault System takes account to the fact that the base of the Zechstein beneath the present Northeast German basin shows hardly any evidence for brittle deformation, which indicates a relative stable basement. Our geomechanical model suggests that the Permocarboniferous deposits may have contributed to the structural stiffness by covering small to medium scale structures of the upper parts of the brittle basement. It is further suggested that the pre-Zechstein successions underneath the present Northeast German basin were possibly strengthening during the Cretaceous basin inversion, which resulted in stress transfer to the long-lived master faults, as indicated for example by the shape of the salt domes in the vicinity of the latter faults. Contrary to this, post-Zechstein successions deformed in a different and rather complex way that was strongly biased by intensive salt tectonic movements. 相似文献
3.
Alicja Wudarska Ewa Saby Michael Wiedenbeck Jaime D. Barnes Magali Bonifacie Neil C. Sturchio Grard Bardoux Frdric Couffignal Johannes Glodny Linnea Heraty Timm John Christof Kusebauch Sathish Mayanna Franziska D. H. Wilke Ewa Deput 《Geostandards and Geoanalytical Research》2021,45(1):121-142
Here we report on a set of six apatite reference materials (chlorapatites MGMH#133648, TUBAF#38 and fluorapatites MGMH#128441A, TUBAF#37, 40, 50) which we have characterised for their chlorine isotope ratios; these RMs span a range of Cl mass fractions within the apatite Ca10(PO4)6(F,Cl,OH)2 solid solution series. Numerous apatite specimens, obtained from mineralogical collections, were initially screened for 37Cl/35Cl homogeneity using SIMS followed by δ37Cl characterisation by gas source mass spectrometry using both dual‐inlet and continuous‐flow modes. We also report major and key trace element compositions as determined by EPMA. The repeatability of our SIMS results was better than ± 0.10‰ (1s) for the five samples with > 0.5 % m/m Cl and ± 0.19‰ (1s) for the low Cl abundance material (0.27% m/m). We also observed a small, but significant crystal orientation effect of 0.38‰ between the mean 37Cl/35Cl ratios measured on three oriented apatite fragments. Furthermore, the results of GS‐IRMS analyses show small but systematic offset of δ37ClSMOC values between the three laboratories. Nonetheless, all studied samples have comparable chlorine isotope compositions, with mean 103δ37ClSMOC values between +0.09 and +0.42 and in all cases with 1s ≤ ± 0.25. 相似文献
4.
Hartmut H. Hellmer Monika Rhein Günther Heinemann Janna Abalichin Wafa Abouchami Oliver Baars Ulrich Cubasch Klaus Dethloff Lars Ebner Eberhard Fahrbach Martin Frank Gereon Gollan Richard J. Greatbatch Jens Grieger Vladimir M. Gryanik Micha Gryschka Judith Hauck Mario Hoppema Oliver Huhn Torsten Kanzow Boris P. Koch Gert König-Langlo Ulrike Langematz Gregor C. Leckebusch Christof Lüpkes Stephan Paul Annette Rinke Bjoern Rost Michiel Rutgers van der Loeff Michael Schröder Gunther Seckmeyer Torben Stichel Volker Strass Ralph Timmermann Scarlett Trimborn Uwe Ulbrich Celia Venchiarutti Ulrike Wacker Sascha Willmes Dieter Wolf-Gladrow 《Ocean Dynamics》2016,66(11):1379-1413
5.
From 1998 to 2002 investigations were carried out to estimate both the quantity and quality (heavy metal contents) of suspended matter loads discharged into a floodplain area measuring approx. 5 km2 of the Central German river Weiße Elster, a tributary of the river Saale in the Elbe river basin. Flood sediments, suspended particulate matter, and floodplain soils were investigated especially for the main pollutants Cd, Zn, Cu, Pb, Cr, and Hg. Supplementary gamma spectroscopy examinations were performed to help to identify the age of deposits in order to estimate sedimentation rates for last decades. The recent flood sediments are contaminated by up to 33 times the geogenic background (Cd). Up to 55% of the total annual SPM load of the river Weiße Elster is relocated into the investigated retention area in the flood‐stricken year 2002. The sedimentation rates for the last 50 years vary between 0.5 mm/a and 1 mm/a in far away and rarely flooded parts and between 1 mm/a and 2 mm/a in the frequently flooded parts of the inflow of the retention area. 相似文献
6.
7.
Robust estimates of magnetotelluric and geomagnetic response functions are determined using the coherency and expected uniformity of the magnetic source field as quality criteria. The method is applied on data sets of three simultaneously recording sites. For the data acquisition we used a new generation of geophysical equipment (S.P.A.M. MkIII), which comprises novel concepts of parallel computing and networked, digital data transmission. The data-processing results show that the amount of noise on the horizontal components of the magnetic field varies considerably in time, between sites and over the frequency range. The removal of such contaminated data beforehand is essential for most data-processing schemes, as the magnetic channels are usually assumed to be free of noise. The standard remote reference method is aimed at reducing bias in response function estimates. However, this does not necessarily improve their precision as our results clearly show. With our method, on the other hand, we can filter out source field irregularities, thereby providing suitable working conditions for the robust algorithm, and eventually obtain considerably improved results. Contrary to previous concepts, we suggest rejecting as much data as feasible in order to concentrate on the remaining parts of high-quality observations. 相似文献
8.
In climate and weather prediction models the near-surface turbulent fluxes of heat and momentum and related transfer coefficients are usually parametrized on the basis of Monin–Obukhov similarity theory (MOST). To avoid iteration, required for the numerical solution of the MOST equations, many models apply parametrizations of the transfer coefficients based on an approach relating these coefficients to the bulk Richardson number \(Ri_{b}\). However, the parametrizations that are presently used in most climate models are valid only for weaker stability and larger surface roughnesses than those documented during the Surface Heat Budget of the Arctic Ocean campaign (SHEBA). The latter delivered a well-accepted set of turbulence data in the stable surface layer over polar sea-ice. Using stability functions based on the SHEBA data, we solve the MOST equations applying a new semi-analytic approach that results in transfer coefficients as a function of \(Ri_{b}\) and roughness lengths for momentum and heat. It is shown that the new coefficients reproduce the coefficients obtained by the numerical iterative method with a good accuracy in the most relevant range of stability and roughness lengths. For small \(Ri_{b}\), the new bulk transfer coefficients are similar to the traditional coefficients, but for large \(Ri_{b}\) they are much smaller than currently used coefficients. Finally, a possible adjustment of the latter and the implementation of the new proposed parametrizations in models are discussed. 相似文献
9.
Patrizia Köpfli Lorenz M. Grämiger Jeffrey R. Moore Christof Vockenhuber Susan Ivy-Ochs 《Swiss Journal of Geoscience》2018,111(1-2):205-219
Landslide deposits dam Lake Oeschinen (Oeschinensee), located above Kandersteg, Switzerland. However, past confusion differentiating deposits of multiple landslide events has confounded efforts to quantify the volume, age, and failure dynamics of the Oeschinensee rock avalanche. Here we combine field and remote mapping, topographic reconstruction, cosmogenic surface exposure dating, and numerical runout modeling to quantify salient parameters of the event. Differences in boulder lithology and deposit morphology reveal that the landslide body damming Oeschinensee consists of debris from both an older rock avalanche, possibly Kandertal, as well as the Oeschinensee rock avalanche. We distinguish a source volume for the Oeschinensee event of 37 Mm3, resulting in an estimated deposit volume of 46 Mm3, smaller than previous estimates that included portions of the Kandertal mass. Runout modeling revealed peak and average rock avalanche velocities of 65 and 45 m/s, respectively, and support a single-event failure scenario. 36Cl surface exposure dating of deposited boulders indicates a mean age for the rock avalanche of 2.3 ± 0.2 kyr. This age coincides with the timing of a paleo-seismic event identified from lacustrine sediments in Swiss lakes, suggesting an earthquake trigger. Our results help clarify the hazard and geomorphic effects of rare, large rock avalanches in alpine settings. 相似文献
10.
Ulrike?WackerEmail author K.?V.?Jayaraman?Potty Christof?Lüpkes J?rg?Hartmann Matthias?Raschendorfer 《Boundary-Layer Meteorology》2005,117(2):301-336
The mesoscale weather prediction model ’Lokal-Modell’ (LM) of the Deutscher Wetterdienst is applied to the situation of an
Arctic cold air outbreak in the Fram Strait region in April 1998. Observations are available from a flight along 50E carried out during the ARTIST campaign. Initial and time-dependent boundary data for the simulation are taken from a larger
scale operational model system.
Using the standard configuration of LM, the simulation reproduced the propagation of cold air and the characteristic structure
of the atmospheric boundary layer (ABL) in fair agreement with the observations. However, a detailed comparison revealed three
basic problems. Firstly, there is evidence that the available data on sea-ice conditions were insufficient approximations
to the true state for several reasons. A modification of the sea-ice data towards observations revealed that parts of the
discrepancies were due to the original sea-ice data. Secondly, a control run with the model in its standard configuration
shows an insufficient warming of the ABL downstream of the ice edge due to underestimation of surface heat fluxes. A simple
modification of the approach for the scalar roughness length resulted in the strongest benefit, while comparative studies
showed only a slight sensitivity to different types of parametrisation of turbulent mixing or the inclusion of an additional
moist convection parametrisation. Thirdly, in all the simulations the deepening of the convective ABL downstream of the ice
edge is weaker than observed. This may be partly due to the thermal stratification above the ABL in the analysis data, which
is more stable than observed; but it may also be a hint to the fact that processes near the inversion are insufficiently parametrised
in mesoscale models with resolutions as used in LM. The simulated cloud layer in the convective ABL is similar to that observed
with respect to condensate content, a sharply defined cloud top, a diffuse lower bound, and continuous light precipitation. 相似文献