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151.
Edward Hall 《Area》2004,36(3):298-306
The social geographies of people with learning disabilities, one of the most marginalized groups in society, have largely been ignored. The paper explores these hidden geographies through the interpretation of narratives of people with learning disabilities in Scotland, within a social policy framework of social exclusion and inclusion. The paper interprets the experiences of being excluded from and included within mainstream socio-spaces, and the safe spaces that many people with learning disabilities have formed for themselves in between the positions of social exclusion and inclusion.  相似文献   
152.
The prime causation of the mid-Late Devonian mass extinction near the Frasnian–Famennian (F–F) boundary remains uncertain. Nevertheless, geochemical evidence has been presented recently as decisive evidence of a giant bolide impact occurring precisely at the F–F boundary, which promoted the global mortality episode. Palaeobiological data, however, imply a gradual global change, which is otherwise seen as a record of either multiple extraterrestrial catastrophes or of impact-triggered Earth-bound mechanisms. Sedimentological (mega-tsunami), physical (craters, microtektites), and geochemical records remain either elusive in many aspects, or incompatible with the predicted impact crisis pattern. Biotic succession across the F–F horizon is still poorly known, especially in continental domains, to evidence a synchronous ("bedding-plane") killing event at the close of the crisis. Instead, the commonly documented stepwise loss of biomass and an unproved distinctive "dead zone" are hard to explain simply as sampling artifacts. The assumed mass mortality precisely at the F–F boundary may be limited mainly to the pelagic realm. The underestimated role of early Variscan tectonism and associated volcanic-hydrothermal processes, resulting in thermal and nutrient pulses, as possible prime controls of the F–F crisis is suggested, as well as resemblances to the superplume-conditioned eventful mid-Cretaceous interval, exemplified in the Cenomanian-Turonian mass extinction. Additional shocks, generated by minor cometary strikes, are not excluded but may have affected some F–F biotas or areas. Received: 9 June 1998 / Accepted: 2 November 1998  相似文献   
153.
This paper explores the campaigning culinary documentary (CCD) as an emerging format within food television. CCDs bring together elements of the lifestyle genre with an explicit focus on a food ‘crisis’ – such as obesity or animal welfare – and explore how this crisis is to be resolved, usually through the intervention of a food celebrity. Focussing largely on shows made by the UK’s Channel 4 network, we explore the ways in which CCDs narrate issues of responsibilization, whether these target consumers/viewers, the food industry, or the state. Through a reading of selected CCDs from Channel 4’s roster, we consider how the shows attempt to fuse elements of lifestyle/reality TV with a social or political agenda, but one which deploys the governmental strategy of responsibilization and so could be read as an enactment of neoliberal logic. While there is some truth to this claim, our analysis and discussion seeks to complicate this reading, showing how CCDs open up other narrative and political possibilities while also consolidating the brand image of the cookery TV stars who front them.  相似文献   
154.
The remains of trilobites and other species were unexpectedly discovered in a volcanic ash layer beneath the Permian–Triassic Boundary (PTB). Based on a biostratigraphic investigation of the Zhongliangshan section in Chongqing, South China, the quantity of the species gradually decreased with subsequent volcanism. This finding provides an opportunity to further understand the disappearance of trilobites and the evolution of the mass extinction event. The temporal coincidence between the volcanic eruption event and the loss of trilobites and other species supports the idea of a cause-and-effect relationship. The species remains in the ash bed appeared before the disappearance of Clarkina yini and the climax of the negative carbon isotope excursion, which implies that the onset of the mass extinction occurred at the end-Permian. The explosive volcanic events caused massive releases of CO2, toxic gases and volcanic ash and resulted in loss of habitat for certain species in the Tethys domain. This phenomenon may have led to the abrupt death of trilobites and the catastrophic collapse of biodiversity.  相似文献   
155.
A multi-scale analysis of sedimentary carbonate facies and post-sedimentary diagenetic features of the Calcare di Base Formation, the precursor to evaporites in Upper Messinian successions of Northern Calabria and Central Sicily, has revealed their microbial bio-mediated origin. Massive to laminated microbial boundstones represent the most common sedimentary facies forming flat to low relief cm to m scale stromatolitic and thrombolitic bodies. The fabric of the micrite varies from peloidal to aphanitic, and almost always preserves filamentous bacteria which characterized the original microbial mat. The mat was dominated by sulphur-oxidizing bacteria belonging to the Thiotrichaceae, but there is evidence for a more complex community with sulphate- and/or nitrate-reducing bacteria, all being responsible for the mediation of the carbonate precipitation. Microbial boundstones are rich in pseudomorphs of Ca-sulphate and halite, which formed during the deposition of the microbial carbonate. Layers of primary gypsum are interbedded locally with carbonates suggesting the presence of restricted marine conditions. The stable O and C isotopic composition of the carbonates, that vary from dolomite to aragonite and calcite, suggests a complex interplay between arid to humid climatic changes, expressed cyclic interbedding of the carbonate with marl-marlstone. Later diagenetic events mainly consist of phreatic meteoric recrystallization and cementation. Although considered as diachronous, the microbial carbonates can be mapped out over a distance of more than 500 km across southern Italy; this indicates near-constant environmental conditions upon the central Mediterranean shelf at the beginning of the salinity crisis. Deposition of the extensive subaqueous microbial deposit that largely comprises the Calcare di Base is envisaged to have taken place across a shallow to moderate depth platform with local slopes into deeper water areas, where some resedimentation occurred.  相似文献   
156.
焦诚中 《吉林地质》2000,19(2):4-14
中国作为一个世界上最大的发展中国家,它的可持续发展的实质是其现代化进程能否持续下去,进而最终实现现代化。中国的现代化对矿产资源的需求趋势及矿产资源的严重匮乏将导致我国现代化中断的现实,突显出我国矿产资源战略必须实行大的调整这一紧迫的问题,改变目前现行的主要依靠自己的力量,开源节流,利用两个市场、两种资源的保障格局, 向利用国外资源为主兼顾利用国内资源为辅的资源保障战略。本文对国内帮产资源的现状及战  相似文献   
157.
The onshore–offshore correlation of sedimentary successions is a common problem in basin analysis, but it becomes critical for the full understanding of the Messinian salinity crisis (MSC), a complex array of palaeoenvironmental events which affected the Mediterranean basin at the end of the Miocene. The outcrop records show that the Messinian stratigraphic architectures may be highly complex as the deposits of the different MSC evolutionary stages can be lithologically similar and separated by erosional surfaces and/or morphostructural highs. The correct definition of the nature and stratigraphic position of Messinian deposits in offshore areas through seismic data may be almost impossible, especially where core data are sparse. To bridge the gap between onshore and offshore records, we have built synthetic seismic sections from well‐constrained outcrop successions. Our results provide useful insights and warnings for the interpretation of offshore data, pointing out that MSC units having different age, nature and depositional settings, may show similar seismic facies and geometries. Conversely, the same deposit may result in different seismic facies, either with parallel and high‐amplitude reflections or even transparent or chaotic due to interference patterns of seismic reflections related to dominant frequency. It follows that a correct interpretation of the nature and age of deep‐seated Messinian deposits can only be obtained through the integration of seismic and core data, and considering the onshore record. The application of our approach to the Balearic Promontory results in an alternative interpretation with respect to previous models. We show that this offshore area has good analogues in the onshore of the Betic Cordillera and includes both shallow and intermediate depth sub‐basins that underwent a strong post‐Messinian subsidence.  相似文献   
158.
樊杰  陈东  吕晨 《地理研究》2009,28(6):1439-1448
国际金融危机是地域空间上发生、空间拓展及区域响应过程非常迅速的新经济地理事像,探究其在特定地点发生的机制、区域影响的空间拓展过程、区域受损响应的规律及长期区域对策,是经济地理学的一个新命题。鉴于金融危机事像成因和演变的经济属性强、空间过程和区域响应的经济驱动机理显著,尝试采用"微观经济—宏观经济—区域经济"一个新的研究范式进行探讨。从微观虚拟经济企业对利润的无限追求-宏观虚拟经济与实体经济的价值脱节和政府监控不到位-特定区域金融危机的爆发,发达国家微观企业产业组织-宏观国际产业链分工-金融危机的空间扩散,微观消费者边际效用损失的差异和灾变点的存在-宏观实体经济和虚拟经济对自然资源和人力资本的依赖以及经济的可恢复能力-区域金融危机的差异化响应等方面,初步探讨了金融危机的空间过程,提出了"1元≠1元"的经济地理损失效应判断,据此探讨了差异化的区域响应规律,得出以资源环境为代价换取经济增长、生活相对不富裕的地域在金融危机中受损程度可能更大的初步结论,提出了现代服务业据点式突破在空间结构组织上具有可能的研究假设。最后,就提高经济增长的人力资本贡献度、提升内需的拉动作用等应对全球化风险的长期策略进行了阐释。  相似文献   
159.
The study of rock samples from the Upper Permian Khei-Yaga River section revealed an r-n-r-n-r magnetic polarity succession based on the prefolding characteristic component of natural remanent magnetization. With account for stratigraphic and previous magnetostratigraphic data on Lower Triassic rocks from the Khei-Yaga River section, the examined strata of the Pechora Group (Silova Formation) may be compared with magnetic zones R1P2u and N1P3t in the magnetostratigraphic scale of European Russia. The gap in the paleomagnetic record, which corresponds in the examined section to the interval of the mid-Severodvinian Stage to basal Induan Stage, Zone N1T included, is estimated to be 10 Ma long. It is assumed that this hiatus represents one of the local signs of the global Permian-Triassic crisis.  相似文献   
160.
We present the results of a study of the Vena del Gesso Basin (Romagna Apennines, Italy) integrating field analyses and analogue modelling. This basin represents one of the best‐preserved top‐thrust basins in the Northern Apennines foreland and is one of the few examples where primary evaporites, related to the Messinian salinity crisis of the Mediterranean, widely crop out. The structural style affecting the Messinian gypsum is examined to get insights into the mechanism responsible for the overall deformation features recognizable in the area. The evaporites are completely detached at the base and widespread back‐thrusts, repeatedly doubling these deposits, strongly contrast with the regional forelandward vergence of structures in the Apennines. On the basis of the comparison between field data and experimental results, the features characterising this area can be described as the result of the deformation linked to the sequential activation of an obliquely propagating passive‐roof duplex. Analogue models evidenced the major role played (1) by syntectonic erosion that promoted the development of passive‐roof duplex style, as well as (2) the role of décollement level pinch‐out that determined an oblique progression of deformation. Finally our data lead to reconsider the palaeoenvironmental reconstruction concerning the onset of the Messinian salinity crisis in the Mediterranean. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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