全文获取类型
收费全文 | 393篇 |
免费 | 27篇 |
国内免费 | 7篇 |
专业分类
测绘学 | 5篇 |
大气科学 | 26篇 |
地球物理 | 70篇 |
地质学 | 181篇 |
海洋学 | 20篇 |
天文学 | 56篇 |
综合类 | 2篇 |
自然地理 | 67篇 |
出版年
2024年 | 1篇 |
2023年 | 3篇 |
2022年 | 11篇 |
2021年 | 14篇 |
2020年 | 19篇 |
2019年 | 14篇 |
2018年 | 12篇 |
2017年 | 16篇 |
2016年 | 22篇 |
2015年 | 17篇 |
2014年 | 15篇 |
2013年 | 31篇 |
2012年 | 25篇 |
2011年 | 36篇 |
2010年 | 21篇 |
2009年 | 18篇 |
2008年 | 27篇 |
2007年 | 11篇 |
2006年 | 17篇 |
2005年 | 14篇 |
2004年 | 14篇 |
2003年 | 7篇 |
2002年 | 11篇 |
2001年 | 8篇 |
2000年 | 5篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1983年 | 2篇 |
1980年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1973年 | 3篇 |
1969年 | 1篇 |
1962年 | 1篇 |
排序方式: 共有427条查询结果,搜索用时 15 毫秒
361.
Peloponnesus in the south-western part of the Aegean is formed by a heterogeneous pile of alpine thrust sheets that was reworked
by normal faulting from Upper Miocene to recent times. Upper Miocene–Lower Pliocene extension in Mt Parnon was accommodated
by several mappable brittle detachment faults that exhibit a top-to-the-NE-ENE sense of shear. The hanging wall of the detachments
comprises a number of highly tilted fault blocks containing abundant evidence of intense internal deformation by normal faulting
and layer-parallel shearing contemporaneous with faulting. These fault blocks are remnants of a cohesive extensional block
that slipped to the NE-ENE and broke up along high-angle normal faults that sole into or are cut by the detachments. The largest
part of this block is located at the eastern edge of the metamorphic core forming the hanging wall of East Parnon high-angle
normal fault that excised part of the aforementioned detachments. The lowermost metamorphic Unit of the nappe-pile does not
seem to be affected by the previous extensional episode. Upper plate reconstruction shows that various units of the nappe-pile
were affected by high-angle normal faults that linked to detachment faults in the weaker layers. Since the Middle-Upper Pliocene
further exhumation of the metamorphic rocks has resulted in the formation of high-angle normal faults overprinting Neogene
extensional structures and cut the entire nappe-pile. This new fault system tilted the earlier extensional structures and
produced a NE-SW coaxial deformation of Mt Parnon. 相似文献
362.
Turbiditic levee deposition in response to climate changes: The Var Sedimentary Ridge (Ligurian Sea)
Stéphan J. Jorry Isabelle Jégou Laurent Emmanuel Ricardo Silva Jacinto Bruno Savoye 《Marine Geology》2011,279(1-4):148-161
The Var turbiditic system located in the Ligurian Sea (SE France) is an intermediate mud/sand-rich system. The particularity of the Var deep-sea fan is its single channel with abrupt bends and its asymmetric and hyper-developed levee on the right hand side: the Var Sedimentary Ridge. Long-term sediment accumulation on the Var Sedimentary Ridge makes this an ideal target for studying the link between onshore climate change and deep-sea turbidite stratigraphy. This paper focuses on the establishment of the first detailed stratigraphy of the levee, which is used to analyze the timing of overbank deposition throughout the last deglaciation. Main results indicate that high variability in turbidite frequencies and deposition rates along the Var Sedimentary Ridge are determined by two main parameters: 1) the progressive decrease of the levee height controlling the ability of turbidity currents to spill out from the channel onto the levee, and 2) climatic variations affecting the drainage basin, in particular changes in glacial condition since late Last Glacial Maximum to early Holocene. Compared to other deep-water areas, this study confirms the ability of turbiditic systems to record past climatic events on millennial timescales, and underlines the influence of European deglaciation on the observed decrease in turbidite activity in the Var canyon. The presence of a very narrow continental shelf and a single, large channel-levee system makes the Var Sedimentary Ridge a unique example of climate-controlled turbiditic accumulations. 相似文献
363.
364.
A Compilation of Silicon and Thirty One Trace Elements Measured in the Natural River Water Reference Material SLRS-4 (NRC-CNRC) 总被引:1,自引:0,他引:1
Delphine Yeghicheyan Jean Carignan Michel Valladon Martine Bouhnik Le Coz Florence Le Cornec Maryse Castrec-Rouelle Michel Robert Luc Aquilina Emmanuel Aubry Carine Churlaud Aline Dia Samuel Deberdt Bernard Dupré Rémi Freydier Gérard Gruau Odile Hénin Anne-Marie de Kersabiec Joël Macé Luc Marin Nicole Morin Patrice Petitjean Elodie Serrat 《Geostandards and Geoanalytical Research》2001,25(2-3):465-474
The natural river water certified reference material SLRS-4 (NRC-CNRC, National Research Council-Conseil National de Recherches Canada) has been routinely analysed for major and trace elements by six French laboratories. Most measurements were made using inductively coupled plasma-mass spectrometry. For silicon and thirty one trace elements (rare earth elements, Ag, B, Br, Cs, Ga, Ge, Li, P, Pd, Rb, Se, Th, Ti, Tl, W, Y and Zr), no certified values are assigned by NRC-CNRC. We propose some compilation values and related uncertainties according to the results obtained by the different laboratories. 相似文献
365.
Teacher''s Aide Variogram Interpretation and Modeling 总被引:13,自引:0,他引:13
The variogram is a critical input to geostatistical studies: (1) it is a tool to investigate and quantify the spatial variability of the phenomenon under study, and (2) most geostatistical estimation or simulation algorithms require an analytical variogram model, which they will reproduce with statistical fluctuations. In the construction of numerical models, the variogram reflects some of our understanding of the geometry and continuity of the variable, and can have a very important impact on predictions from such numerical models. The principles of variogram modeling are developed and illustrated with a number of practical examples. A three-dimensional interpretation of the variogram is necessary to fully describe geologic continuity. Directional continuity must be described simultaneously to be consistent with principles of geological deposition and for a legitimate measure of spatial variability for geostatistical modeling algorithms. Interpretation principles are discussed in detail. Variograms are modeled with particular functions for reasons of mathematical consistency. Used correctly, such variogram models account for the experimental data, geological interpretation, and analogue information. The steps in this essential data integration exercise are described in detail through the introduction of a rigorous methodology. 相似文献
366.
Costas Emmanuel Synolakis 《Natural Hazards》1991,4(2-3):221-234
This is a study of the application of linear theory for the estimation of the maximum runup height of long waves on plane beaches. The linear theory is reviewed and a method is presented for calculating the maximum runup. This method involves the calculation of the maximum value of an integral, now known as the runup integral. Laboratory and numerical results are presented to support this method. The implications of the theory are used to reevaluate many existing empirical runup correlations. It is shown that linear theory predicts the maximum runup satisfactorily. This study demonstrates that it is now possible to match complex offshore wave-evolution algorithms with linear theory runup solutions for the purpose of obtaining realistic tsunami inundation estimates. 相似文献
367.
Gorka?Landeras Emmanuel?Bekoe Joseph?Ampofo Frederick?Logah Mbaye?Diop Madiama?Cisse Jalal?ShiriEmail authorView authors OrcID profile 《Theoretical and Applied Climatology》2018,132(3-4):701-716
Accurate estimation of reference evapotranspiration (ET 0 ) is essential for the computation of crop water requirements, irrigation scheduling, and water resources management. In this context, having a battery of alternative local calibrated ET 0 estimation methods is of great interest for any irrigation advisory service. The development of irrigation advisory services will be a major breakthrough for West African agriculture. In the case of many West African countries, the high number of meteorological inputs required by the Penman-Monteith equation has been indicated as constraining. The present paper investigates for the first time in Ghana, the estimation ability of artificial intelligence-based models (Artificial Neural Networks (ANNs) and Gene Expression Programing (GEPs)), and ancillary/external approaches for modeling reference evapotranspiration (ET 0 ) using limited weather data. According to the results of this study, GEPs have emerged as a very interesting alternative for ET 0 estimation at all the locations of Ghana which have been evaluated in this study under different scenarios of meteorological data availability. The adoption of ancillary/external approaches has been also successful, moreover in the southern locations. The interesting results obtained in this study using GEPs and some ancillary approaches could be a reference for future studies about ET 0 estimation in West Africa. 相似文献
368.
Emmanuel John M. Carranza 《Natural Resources Research》2017,26(4):411-428
According to previous studies, the use of enrichment factors in environmental studies is inconsistent with its original concept and that such indiscriminate use of enrichment factors should be stopped. In this contribution, it is shown through spatial correlation analysis that using enrichment factors is no better than using log-ratios of geochemical data for mapping of deposit-related anomalies. 相似文献
369.
Emmanuel John M. Carranza 《Natural Resources Research》2017,26(4):379-410
In its 26 years of existence, the journal of Natural Resources Research (NRR) has published and continues to publish papers on geochemical anomaly and mineral potential mapping. This is consistent with its aims and scope to publish quantitative studies of natural (mainly but not limited to mineral) resources exploration, evaluation and exploitation, including environmental and risk-related aspects. Over the years, NRR has contributed significantly more to the publication of developments in mineral potential mapping and notably less to the publication of developments in geochemical anomaly mapping. In more detail, NRR has contributed significantly more to the publication of research on development of robust quantitative methods for analysis and synthesis of spatial evidence of mineral potential but notably less to the publication of research on development of geologically focused models of mineral potential. The editorship of NRR recognizes the latter as a challenge to promote further research on development of numerically robust as well as geologically focused mineral potential models, and this special issue is a major initiative in response to that challenge. The recent inclusion of Natural Resources Research for coverage by the Clarivate Analytics (formerly the Institute for Scientific Information) in the Science Citation Index Expanded? and Journal Citation Reports® (JCR) Science Edition will help make Natural Resources Research meet that challenge. 相似文献
370.
Karamzadeh Nasim Lindner Mike Edwards Benjamin Gaucher Emmanuel Rietbrock Andreas 《Journal of Seismology》2021,25(6):1385-1406
Journal of Seismology - Monitoring small magnitude induced seismicity requires a dense network of seismic stations and high-quality recordings in order to precisely determine events’... 相似文献