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V.R. BELYAEV E. A. EREMENKO A. V. PANIN Y. R. BELYAEV 《国际泥沙研究》2005,20(3):224-232
Two gullies located in the Protva River basin (central part of European Russia, 100 Ion southwest of Moscow) were studied to investigate the history of their development during Late Holocene. This case study included detailed topographic and geomorphologic surveys, geological cross-sections, and radiocarbon dating of organic matter in gully sediments. For both gullies, incision of the long profile occurred for most of the Holocene, as indicated by the limited presence of infill sediment. However, interruptions of incisions occurred in both gullies during the last -3.5 ka (the Chugunkin gully) or -2.0 ka (the Uzkiy gully), as evident from stratigraphic interpretation of the sediment record. Periods of surface stabilization are represented by buried soil horizons, whereas relatively thick sediment layers suggest periods of predominant aggradation. Similarities and differences in discovered sequences of erosion and accumulation stages for the two gullies point out the importance of distinguishing between local and regional controls. Evidence of the role of internal system behavior and self-development in the gully long-term evolution is clear from asynchronous response of different parts of gullies. In recent times (-500 years), active agricultural development of the study territory resulted in accelerated incisions, followed by deposition of catchment-derived material. The latter was limited to the upper parts of the gullies, while incisions have continued in the middle and lower parts. The impact of human activities (-500 years) has been very limited. This suggests that within the forest zone of the Russian Plain many gullies which were earlier attributed to anthropogenic factors are, in realitv, due to natural phenomena. 相似文献
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G. J. HANSON D. M. TEMPLE K. M. ROBINSON K. R. COOK 《国际泥沙研究》2005,20(3):259-269
Traditionally gully erosion has been identified with the dissection of the landscape in agricultural settings but it is also recognized as a prevalent erosion feature in earthen dam auxiliary spillways and embankments. Flows through earthen spillways and over dam embankments, due to large rainfall events, have the potential to erode and breach the dam or spillway and result in catastrophic releases from the reservoir. The gully erosion process in an earthen spillway or on an embankment can be characterized by stages of initiation, development, and migration of a headcut. A headcut is defmed as a near vertical drop at the upstream end of a gully. The rate of headcut migration is important in determining the breach potential of an earthen spillway and dam embankment. A research program is being conducted to examine the gully erosion processes of earthen dam auxiliary spillways and embankments. This paper describes: l ) the unique test facilities constructed to examine the dominant factors affecting the erosion of earthen spillways and embankments; 2) the observations of the erosion processes and results to date; and 3) the predictive relationships that have been developed for dam gully erosion research at the ARS Hydraulic Engineering Research Unit laboratory in Stillwater, OK. 相似文献
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北京西北狼山-黄柏寺断裂带几何学分段的冲沟纵剖面标志 总被引:1,自引:2,他引:1
北京西北的狼山-黄柏寺断裂带是延庆盆地北缘正断裂带的西南部分,两个130°—140°的主要弯曲把它分成了走向不同的三个断层段落。 利用Hack的方法分析了沿该断裂带的71条冲沟纵剖面,显示出它们对断层几何学分段很好的地貌响应。在两个弯曲部位,比降指标K值较高。三个断层段落在五值、五值水平分组、裂点(具有高SL/K比值)分级,以及主河长度-面积关系等方面有很大不同。 冲沟纵剖面是正断层几何学分段重要的构造地貌标志,并将为各段落的运动学和古地震学提供认识 相似文献
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