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排序方式: 共有247条查询结果,搜索用时 15 毫秒
211.
荣成地震台钻孔倾斜NS分量2017年5月2日出现趋势下降(南倾)异常变化,至15日持续下降累计幅度达358×10-3",对观测系统工作状态、观测环境干扰、气象因素及地下水位等进行调查,通过滑动相关性分析和三维点源载荷模拟等方法,结合胶东半岛近期地震活动,分析认为,该异常非干扰造成,可能反映了区域地壳应力的变化,需予以关注。 相似文献
212.
正Polyhalite generally formed in the early diagenetic stage.It is formed by the brine which rich in K+and Mg2+and adverse reaction with the gypsum,anhydrite,glauberite(Pierre,1985;Peryt et al.,2005;Leitner et al., 相似文献
213.
214.
本文采用2003~2016年SSMI海冰密集度和NCEP气温、风场等数据,通过计算海冰覆盖率、增长期长度、冬季负积温和风拖曳力等参数,分析了巴伦支海海冰的变化特征及其与热力、动力影响因素之间的联系。结果显示,因西南部存在常年无冰区,巴伦支海14a平均的海冰覆盖率低于50%;覆盖率总体呈现下降趋势,冰情呈现"重—中等—轻"的变化过程,2012年后甚至出现夏季无冰的情况;增长期长度先增后减,起止时刻均有推迟;冬季负积温是影响巴伦支海冰情轻重的重要因素,与年平均海冰覆盖率距平和最大覆盖率的相关系数分别为-0.90和-0.89;风拖曳力的改变可在短期内引起海冰覆盖率急剧变化,是海冰边缘区产生流冰的主要原因,易对油气资源开发的海洋平台产生危害。 相似文献
215.
新疆罗布泊K1孔岩心中有孔虫化石的发现及其意义 总被引:6,自引:0,他引:6
笔者在新疆罗布泊K1孔第四纪沉积物中,首次发现丰富的有孔虫化石(Ammonia)及与其伴生的介形虫和轮藻化石。Ammonia是中新世至观在世界上常见属种,属海陆过渡相种群,第四纪罗布泊已距海遥远,不可能发生海侵,根据塔里木盆地新生代浸侵史,认为罗布泊K1孔第四纪沉积物中有有孔虫来源于残留海。 相似文献
216.
Li Rufeng Liu Benpei Zhao Chenglin University of Petroleum Beijing China University of Geosciences Beijing University of Petroleum Beijing 《《地质学报》英文版》1997,71(2):217-226
In light of the principle of sequence stratigraphy, detailed analysis of depositionalsequences and systematical carbon isotope measurements were done for the Triticites zone ofthe typical Late Carboniferous section in the Dushan area of southern Guizhou. Two sequencesand seventeen parasequences, which can be correlated with the two sequences and seventeensubsequences in the North American Midcontinent, are distinguished in the Gzhelian, whichprovides convincing evidence of the global synchroneity of the depositional records. The inter-nal relations between carbon isotope evolution and eustasy were studied and the evolutionarycharacteristics of carbon isotopes in depositional sequences have been summarized. 相似文献
217.
镁铁橄榄石系列的高压合成及其X射线衍射和红外光谱研究 总被引:3,自引:2,他引:3
橄榄石是上地幔的主要造岩矿物,也是陨石和月岩的重要矿物成分。研究镁铁橄榄石系列矿物,对探讨岩石圈和行星的物质演化、陨石的形成条件等具有重要意义。本实验在30kbar和1000—1200℃的含水条件下,由等化学计量的氧化物合成了从镁端员到铁端员的镁铁橄榄石完整系列矿物共五个样品。并对它们进行了X射线粉晶衍射、化学分析和红外光谱研究。结果表明随Fa值的增加,其晶胞参数呈连续地线性增加,并且有很好的相关关系:a=4.746+7.64×10~(-4)Fa(r=0.999);b=10.172+3.03×10~(-3)Fa(r=0.999);c=5.967+1.03×10~(-4)Fa(r=0.998)。r为相关系数。另外,随Fa值的增加,红外吸收频率降低,也存在着很好的线性相关关系。这表明镁铁橄榄石系列是完全固溶体系列,与镁铁置换有关,与阳离子的占位无关。这表明在合成的橄榄石结构中镁铁的分布基本上是无序的。而镁铁的质量、离子半径和负电性的差异是引起上述参数规律性变化的原因。红外光谱带的分裂则是橄榄石矿物结构中位置对称性降低的必然结果。 相似文献
218.
为提高IGS超快星历钟差预报产品的精度,针对卫星钟差数据具有确定项和随机项成分的特点,在采用多项式模型对钟差确定项建模的基础上,提出采用混沌加权一阶局域法对钟差随机项进行建模预报。仿真结果表明,采用混沌加权一阶局域法的预报精度优于超快星历钟差预报产品。 相似文献
219.
The U.S. Geological Survey procedure for the estimation of the general form of the parent distribution requires that the parameters
of the log-geometric distribution be calculated and analyzed for the sensitivity of these parameters to different conditions.
In this study, we derive the shape factor of a log-geometric distribution from the ratio of frequencies between adjacent bins.
The shape factor has a log straight-line relationship with the ratio of frequencies. Additionally, the calculation equations
of a ratio of the mean size to the lower size-class boundary are deduced. For a specific log-geometric distribution, we find
that the ratio of the mean size to the lower size-class boundary is the same. We apply our analysis to simulations based on
oil and gas pool distributions from four petroleum systems of Alberta, Canada and four generated distributions. Each petroleum
system in Alberta has a different shape factor. Generally, the shape factors in the four petroleum systems stabilize with
the increase of discovered pool numbers. For a log-geometric distribution, the shape factor becomes stable when discovered
pool numbers exceed 50 and the shape factor is influenced by the exploration efficiency when the exploration efficiency is
less than 1. The simulation results show that calculated shape factors increase with those of the parent distributions, and
undiscovered oil and gas resources estimated through the log-geometric distribution extrapolation are smaller than the actual
values. 相似文献
220.
Liu Chenglin Che Changbo Zhu Jie Yang Hulin Fan Bojiang 《Natural Resources Research》2010,19(1):23-31
This paper provides a new method to estimate recovery factors of oil resources. The China National Petroleum Assessment (2003–2007)
(CNPA 2007) evaluates in-place oil resources and applies the recovery factor (RF) to estimate recoverable oil resources. The
RF of oil resources plays an important role in the CNPA 2007. Based on the geological features, 24 types of oil assessment
units are defined, such as the Mesozoic rift unit, the Mesozoic and Cenozoic foreland unit, etc. Through the recovery factor
statistics of oil reserves (discovered) in different accumulations, as well as the potential analyses of enhanced petroleum
recovery, appropriate RF valuing standards of oil resources (discovered and undiscovered) in different assessment units are
developed. Calculation methods of oil resource RFs are established, including the appraisal standards, scoring, and calculation
steps of oil resource RFs. Through the case studies, the valuing and appraisal standards of oil resource RFs are verified.
Robust appraisal standards allow the RF method to be a valuable tool to effective assessment of China’s recoverable oil resources. 相似文献