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961.
"长江三峡水库诱发地震监测研究"项目成果介绍 总被引:6,自引:0,他引:6
本文详细介绍了“长江三峡水库诱发地震监测研究”项目的立项背景、目标、所开展的主要工作、取得的成果、研究成果的社会效益和对该领域研究未来工作的展望。 相似文献
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1INTRODUCTIONTheFenheReservoirwasimpoundedin1961withtotalstoragecapacityof720milionm3.ItisthelargestreservoirinShanxiProvince... 相似文献
965.
依据1980-1992年全国20个省55座水库渔业资源调查数据,运用R型聚类分析和主成分分析方法对48项指标间的层次性进行分析,水库渔业营养类型划分标准的指标层次体系可确定为:第一大层次(水库形态与自然环境)包括地理,气候,水深,面积和体积.土壤.水文等6个小层次;第二大层次(水的理化性质)包括主要离子,磷素,有机物,溶解气体,氮素等5个小层次;第三大层次(生物学)包括浮游植物,浮游动物,初级生产力,鲢鳙生长等4个小层次. 相似文献
966.
根据岩石铸体薄片和扫描电镜观察资料,分析了吐哈盆地台北凹陷中侏罗统储集层的岩性特征。七克台组中上部储集层以岩屑砂岩为主,属于第一岩性段.七克台组下部一西山窑组储集层以长石岩屑砂岩为主,属于第二岩性段.砂岩的岩性特征对储集层的物理性质具有明显的影响作用。 相似文献
967.
水库移民中安置性移民与开发性移民的比较研究 总被引:6,自引:0,他引:6
建国以来, 中国水库移民安置经历了一个从安置性移民向开发性移民转变的过程。分析比较研究两类移民的本质差别, 有助于认识和掌握社会主义市场经济条件下开发性移民的基本规律性。遵循规律, 探讨问题, 促进开发性移民健康发展。 相似文献
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Correlation between rock fabrics and physical properties of carbonate reservoir rocks 总被引:5,自引:0,他引:5
Three carbonate core samples from an oil and gas reservoir of the NW German basin were chosen to study the correlation between
rock fabrics and physical properties of reservoir rocks. Detailed fabric analyses and texture investigations were carried
out as well as laboratory measurements of different physical properties, e.g. density, porosity, permeability, electrical
conductivity, seismic compressional and shear wave velocities. Although the three core samples come from a similar depositional
facies, they show great differences in the occurrence and three-dimensional distribution of the rock fabric elements. These
heterogeneities are the result of various diagenetic and tectonic processes. For the correlation between the rock fabrics
and the physical properties four main rock fabric types have to be considered: (a) major constituents, e.g. fossils, ooides,
peloides and crystals; (b) pore space with different pore types; (c) fractures; and (d) stylolites. The results of the correlation
clearly show that the values and anisotropies of the petrophysical properties are fairly related to the observed fabric elements,
with their different arrangements, spatial distributions and preferred orientations. These results also provide a fundamental
understanding of the petrophysical responses, such as seismics, to the different geological features (e.g. fractures) and
their dynamic changes with pressure, which can be converted to different depths. The knowledge gained from such correlations
may lead to an improved interpretation of geophysical data for hydrocarbon exploration and production and therefore to an
advanced reservoir characterization.
Received: 28 January 1999 / Accepted: 21 June 1999 相似文献
970.
The “free” or “natural” light hydrocarbon composition obtained by thermal extraction-GC of source rock samples is compared with the light fraction generated by pyrolysis products of the kerogens. Even though there are large differences between the composition of the “free” C4–C13 hydrocarbon fraction and the same fraction generated by pyrolysis, some characteristics have been detected which can be used interchangeably for both data types. Visual inspection of gas chromatograms from thermal extracts and pyrolysates indicates that in particular the relative content of m+p xylene corresponds well between these two analytical methods. The source rock samples used are Upper Jurassic marine shales and Middle and Lower Jurassic coals and coaly shales from offshore Mid-Norway and Denmark. More detailed analysis of the data shows that the most effective parameter which can distinguish between different source rock types in both thermal extracts and pyrolysates is the m+p xylene/nC8 ratio. This parameter has been used to derive classification diagrams for interpreting the source of light hydrocarbons of both natural petroleum fluids analysed by gas chromatography and the same fraction generated by pyrolysis of asphaltenes from the fluids.The model was first tested on 17 natural petroleum fluids from Mid-Norway since a comprehensive study of light hydrocarbon distributions already has been published. Further, the parameter was applied to correlate with asphaltene pyrolysates of the fluids from Mid-Norway and a total of 22 natural oils and condensates from the southernmost Norwegian and Danish sectors. 相似文献