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211.
The objective of the study was to carry out an automatic classification of the lithological units of interest using the integration of remote sensing image, in which various objects are spread on, and terrestrial spectral measurement data. Only endmembers of interest are classified using spectral classification methods such as Spectral Angle Mapper. Following the identification of the types of rock and minerals, integration of remote sensing images and spectral measurement data enable spectral classification. In this study, Short Wave Infrared detector images of Advanced Spaceborne Thermal Emission and Reflection Radiometer satellite and spectroradiometer measurements were used. The study area, Gölova with its geological diversity is located in the Kelkit Valley section of the North Anatolian Fault Zone in Northeast of Turkey. Seventeen rock samples were collected and their coordinates were recorded. The samples were categorized via spectral measurements on their thin sections through petrographic analyses. Marble and Meta lava with different lithological were selected as endmembers. SAM was used as the classification method that enables the analysis of the endmember with the threshold value of 0.009 radian for marble and 0.010 radian for metalava. SAM analysis was compared by visual analysis to principle component analysis, decorrelation stretch, band ratio (R: 4/7, G: 4/1, B (2/3) x (4/3)) and band combination analysis (R: 9, G: 4 and B: 5). This study demonstrates that the SAM method can be successfully used in both the integration of remote sensing image and terrestrial spectral measurement data in lithological classification. Both the endmembers of metalava and marbles were detected in the SAM results at the GPS coordinates noted down whilst collecting the rock samples for accuracy assessment.  相似文献   
212.
The UBV photometry of a detached F-type eclipsing binary V505 Persei is presented. The light curve solution by a simple spherical model combined with the radial velocity data from two high resolution spectra by Marschall et al. (1990) reveals that the system is formed with two identical component stars of M 1.2 M in the main sequence close to ZAMS in evolution. They should have about solar metallicity (z 0.017). The isochrones with solar metallicity by Van denBerg (1985) yield an age of about (2.2± 0.5) × 109 yr for the system. The distance of the system should be about 60 pc.  相似文献   
213.
The Edremit Fault Zone (EFZ) forms one of the southern segments of the North Anatolian Fault Zone (NAFZ) at the northern margin of the Edremit Gulf (Biga Peninsula, South Marmara Region, Turkey). Stratigraphic, structural and kinematic results indicate that basinward younging of the fault zone, in terms of a rolling-hinge mechanism, has resulted in at least three discrete Miocene to Holocene deformational phases: the oldest one (Phase 1) directly related to the inactive Kazda? Detachment Fault, which was formed under N–S trending pure extension; Phase 2 is characterised by a strike-slip stress condition, probably related to the progression of the NAFZ towards the Edremit area in the Plio–Quaternary; and Phase 3 is represented by the high-angle normal faulting, which is directly interrelated with the last movement of the EFZ. Our palaeoseismic studies on the EFZ revealed the occurrence of three past surface rupture events; the first one occurred before 13178 BC, a penultimate event that may correspond to either the 160 AD or 253 AD historical earthquakes, and the youngest one can be associated with the 6 October 1944 earthquake (Mw = 6.8). These palaeoseismic data indicate that there is no systematic earthquake recurrence period on the EFZ.  相似文献   
214.
The Upper Jurassic (Tithonian) plattenkalk successions in the Solnhofen/Eichstätt area consist of alternations of thin‐bedded, laminated, fine‐grained, very pure limestones (so‐called ‘flinz beds’) and softer interlayers with slightly lower carbonate contents that are also laminated and show a foliaceous weathering appearance (‘fäule beds’). These successions are world famous for their exceptionally well‐preserved fossils. In contrast to the well‐studied wealth of fossils, little is known about the origin and diagenesis of the host rock. The reason for this discrepancy might lay in the monotonous appearance of these fine‐grained mudstones that require electron microscopical examination. Study of samples from the Solnhofen–Eichstädt area implies that flinz and fäule beds have undergone differential diagenesis. The ultrastructure of the flinz beds is characterized by interlocking microspar crystals, whereas the fäule beds show smaller and less interlocking crystals. The ratios of diagenetically inert trace elements lack clear differences between the two interlayered lithologies. While most authors agree that the flinz–fäule rhythm reflects rhythmically changing environmental conditions, primary rhythms can be taken as proven only where statistically significant differences in diagenetically resistant proxies are found. The absence of clear primary differences between flinz and fäule beds, however, leaves the question of primary differences unsolved. It is concluded that diagenesis has had a strong influence on the genesis of the lithological rhythm, and that any primary rhythm underlying the diagenetically mature rhythm is less clear than generally assumed.  相似文献   
215.
We present the results of the first study to highlight the demography, morphometry and growth rates of Spinimuricea klavereni, a rare Mediterranean endemic gorgonian exceptionally common in shallow depths of the Northeast Marmara Sea. In the study area, this species forms vast populations on rocks, boulders and attached to pebbles/stones/shells on soft substrates between 20 and 45 m depth, with a total average density of 0.3 colonies·m?2 but comprising patches up to 3 colonies·m?2. Colonies, which are on average 42.9 (±20.1) cm in height, can reach up to 110 cm. Unlike other Mediterranean gorgonians, the colonies studied here showed fast growth rates that decreased with increasing colony height, between 1.5–11.1 and 4.96 ± 3.01 cm·year?1 on average. The low necrosis and high growth rates displayed by this species in the Northeast Marmara Sea confirm the previously hypothesized opportunistic behaviour of the species. The unique community consisting of S. klavereni and other rare gorgonian/soft corals has limited distribution in this area and should be considered to be a vulnerable marine ecosystem. Therefore we recommend that some conservation measures are taken, including the prohibition of all fisheries and anchoring over these assemblages.  相似文献   
216.
217.
Bennike, O., Knudsen, K. L., Abrahamsen, N., Böcher, J., Cremer, H. & Wagner, B. 2010: Early Pleistocene sediments on Store Koldewey, northeast Greenland. Boreas, Vol. 39, pp. 603–619. 10.1111/j.1502‐3885.2010.00147.x. ISSN 0300‐9483. Marine Quaternary deposits, here named the Store Koldewey Formation, are found at ~120 m above sea level in northeast Greenland (76°N). The sequence is referred to the Olduvai normal polarity subchron at 1.95–1.78 Ma BP based on palaeomagnetic studies (palaeomagnetically reversed), amino acid epimerization ratios and evidence from marine and non‐marine fossils. The sediments and the fauna show that the sequence was deposited on a mid or inner shelf, and some elements of the marine mollusc and foraminiferal assemblages indicate water temperatures between ?1 and +1 °C and seasonal sea ice cover during deposition. Mean summer air temperatures were around 6 °C higher than at present, as demonstrated by the occurrence of southern extralimital terrestrial species. Well‐preserved remains of land plants indicate that the adjacent land area was dominated by sub‐arctic forest‐tundra with the trees Larix and Betula, shrubs, herbs and mosses. Most of the species represented as fossils have recent circumpolar geographical ranges. An extinct brachiopod species and an extinct gastropod species have been found, but the other macrofossils are referred to extant species. The brachiopod is erected as a new genus and species, Laugekochiana groenlandica. Correlation of the Koldewey Formation with the Île de France Formation farther to the north is suggested. Member A of the Kap København Formation in North Greenland is referred to the Late Pliocene, whereas Member B of the Kap København Formation is suggested to be slightly older than the Store Koldewey Formation.  相似文献   
218.
219.
Anjar, J., Larsen, N. K., Björck, S., Adrielsson, L. & Filipsson, H. L. 2010: MIS 3 marine and lacustrine sediments at Kriegers Flak, southwestern Baltic Sea. Boreas, 10.1111/j.1502‐3885.2010.00139.x. ISSN 0300‐9483. Sediment cores from the Kriegers Flak area in the southwestern Baltic Sea show a distinct lithological succession, starting with a lower diamict that is overlain by a c. 10 m thick clay unit that contains peat, gyttja and other organic remains. On top follows an upper diamict that is inter‐layered with sorted sediments and overlain by an upward‐coarsening sequence with molluscs. In this paper we focus on the clay unit, which has been subdivided into three subunits: (A) lower clay with benthic foraminifera and with diamict beds in the lower part; (B) thin beds of gyttja and peat, which have been radiocarbon‐dated to 31–35 14C kyr BP (c. 36–41 cal. kyr BP); and (C) upper clay unit. Based on the preliminary results we suggest the following depositional model: fine‐grained sediments interbedded with diamict in the lower part (subunit A) were deposited in a brackish basin during a retreat of the Scandinavian Ice Sheet, probably during the Middle Weichselian. Around 40 kyr BP the area turned into a wetland with small ponds (subunit B). A transgression, possibly caused by the damming of the Baltic Basin during the Kattegat advance at 29 kyr BP, led to the deposition of massive clay (subunit C). The data presented here provide new information about the paleoenvironmental changes occurring in the Baltic Basin following the Middle Weichselian glaciation.  相似文献   
220.
Abstract

A parameter estimation method is proposed for fitting probability distribution functions to low flow observations. LL-moments are variants of L-moments that are analogous to LH-moments, which were defined for the analysis of floods. LL-moments give higher weights to the small observations. Expressions are given that relate them to the probability distribution function for the case of normal, Weibull and power distributions. Sampling properties of the LL-moments and of the distribution parameters and quantiles estimated by them are found by a Monte Carlo simulation study. It is shown on an example that the low flow quantile estimates obtained by LL-moments may be significantly different from those obtained by L-moments.  相似文献   
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