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831.
《Geoforum》2015
Emerging research on the increasing significance of consumption in the global South is concerned with its links to the globalizing middle classes. Against the backdrop of optimism invested in the new global middle classes to fuel consumption-led growth, this paper contributes to new debate about the articulations and significance of ethical consumption in the global South. Missing from much current mainstream policy, media and academic debate is acknowledgement of the diversity of the global middle classes and an understanding of how ethical interpretations and behaviour differ in various consumer markets around the world. In response, this paper draws on qualitative research in South Africa’s Western Cape to explore the cultural significance of everyday ethical realities in shaping consumption in the global South. In addition to addressing the relative absence of research into ethical consumption in global South contexts, the paper makes two key contributions based our findings. First, it challenges the tendency, particularly in economic discourses, to generalise about the ‘new’ global middle class consumers by highlighting the significance of locality and context in shaping consumption practices in the Western Cape; specifically it finds that, for diverse middle class consumers, thrift is an important ethical choice and practice determining consumption patterns. Second, it highlights the significance of everyday ethical practices in shaping consumption in the Western Cape, focusing specifically on how thrift is imbricated in concerns with not just economic constraint, but also care, habit and aspiration. The paper concludes with reflections on the wider implications of these findings and suggests that they illustrate a need to theorise ethical consumption from contexts in the global South, on their own terms. 相似文献
832.
C. T. Klootwijk 《Australian Journal of Earth Sciences》2013,60(2):375-405
Palaeomagnetic, rock magnetic and magnetic fabric results are presented for a Carboniferous (Visean to Westphalian) succession of felsic, mainly ignimbritic, volcanic and volcaniclastic rocks from the Rocky Creek Block of the northern Tamworth Belt, southern New England Orogen. Detailed thermal demagnetisation of 734 samples from 64 sites show three groups of magnetic components with low (<300°C), intermediate (300–600°C) and high (500–680°C) unblocking temperature ranges. Well‐defined primary magnetisations have been determined for 28 sites with evidence of four overprint phases. The overprints arise from a mid‐Tertiary weathering event (or possibly recent viscous origin), and from fluid movements associated with the Late Cretaceous opening of the Tasman Sea, thrusting during the Middle Triassic main phase of the Hunter‐Bowen Orogeny, and latest Carboniferous — Early Permian formation of the Bowen‐Gunnedah‐Sydney Basin system. Rock magnetic tests establish that the primary magnetisation carriers in the volcanic rocks are mainly magnetite (predominantly single domain, or pseudo‐single domain, and little or no multidomain) and hematite. Optimal magnetic cleaning is achieved at high to very high temperatures, with subtle, but systematic, directional and statistical differences between primary components derived from the mainly hematite fraction and pseudo‐components derived from the mainly magnetite fraction. The 28 primary magnetisation results are presented as six mean‐site results, summarised below and representing 25 sites, and three single‐site results. Fold tests could be applied to five mean‐site results. These are all positive, but one of these results may represent a secondary magnetisation. The primary magnetisation results define a Visean to Westphalian pole path. This long pole path indi cates extensive latitudinal and rotational movement for the Rocky Creek Block, and potentially for the New England Orogen, as follows: (i) Yuendoo Rhyolite Member (Caroda Formation, Visean) pole 235.8°E, 27.7°S, ED95 = 9.0°, n = 3; (ii) Peri Rhyolite Member/Boomi Rhyolite Member (Clifden Formation, Namurian, 318.0 ± 3.4 Ma) pole 177.4°E, 63.4°S, ED95 = 5.2°, n = 3; (iii) tuffaceous beds above Boomi Rhyolite Member (Clifden Formation?, Namurian) pole 162.2°E, 59.1°S, ED95 = 10.2°, n = 3; ((iv) upper Clifden Formation/lower Rocky Creek Conglomerate (Namurian/Westphalian) pole 95.3°E, 49.6°S, ED95 = 8.1°, n = 3 (possible overprint)); (v) Rocky Creek Conglomerate (Westphalian) pole 136.5°E, 57.6°S, ED95 = 5.3°, n = 5; (vi) Lark Hill Formation (Westphalian) pole 127.0°E, 50.4°S, ED95 = 4.8°, n = 8. 相似文献
833.
《Australian Journal of Earth Sciences》2013,60(6):931-954
Carboniferous (Visean to Westphalian) pyroclastics and lava flows in the Rocky Creek region, used to redefine the base of the Kiaman reversal, are formally defined or redefined and the status of the main formations clarified. These units include the Caroda Formation, containing the Kooringal Dacite, Boomi Rhyolite and Barney Springs Andesite Members; the Clifden Formation with the Wanganui Andesite, Glen Idle Rhyolite, Appleogue Dacite, Bexley Rhyolite, Pine Cliffs Rhyolite and Downs Rhyodacite Members; Rocky Creek Conglomerate with the Hazelvale Rhyodacite, Mt Hook Rhyolite, Darthula Rhyodacite and Pound Rock Rhyodacite Members; and Lark Hill Formation with the Eulowrie Pyroclastic, Tycannah Rhyodacite and The Tops Rhyolite Members; a number of informal units are also described. The restriction of most volcanic units to one of the three thrust blocks (Boomi, Kathrose and Darthula blocks) of the Rocky Creek region, suggests their current relationships reflect either shortening due to overthrusting or an original distribution affected by depositional or erosional processes. A westerly increase in the proportion of ignimbrites indicates nearness to sources in that direction. Intermediate volcanism, largely confined to southern and central parts of the Boomi block in the east, began in the Visean and ended in the early Namurian. Acid volcanism also began in the Visean in the northern Boomi block but, with the exception of the Peri Rhyolite Member of the Clifden Formation, did not become widespread until later in the Namurian and Westphalian. In contrast, only acid volcanism took place during the early Namurian to Westphalian in the Kathrose and Darthula blocks. Correlations based on AS3 and SL13 SHRIMP dates illustrate a discordance of about 3% when compared with the most likely location for the base of the Kiaman reversal. The bases of both the Rocky Creek Conglomerate and Lark Hill Formation appear to be slightly diachronous. 相似文献
834.
Geological mapping of fault systems on the Gazelle Peninsula, eastern New Britain arc, combined with a reinterpretation of existing sea floor data indicate that faults previously thought to be a possible location of the boundary between the North and South Bismarck Plates, do not appear to be directly related to the plate boundary spreading centres and transform faults in the 3.5 Ma Manus Basin. Structure on the Gazelle Peninsula is dominated by the Mediva Fault (new name) and the Wide Bay Fault System, both north‐northwest trending, deep‐seated features. The Mediva Fault, an element of the Baining Mountain Horst and Graben Zone, is an extensional structure which has focused Middle Miocene intrusive activity, controlled Mio‐Pliocene sedimentation in the central Gazelle Peninsula, and displaced Quaternary volcanic deposits. The Wide Bay Fault System has been active since at least the Late Oligocene. One hundred kilometres of sinistral strike‐slip motion is likely on this fault since at least the late Middle Miocene, moving the Gazelle Peninsula in a north‐northwest direction with respect to the remainder of New Britain. The nature and timing of movements along these two major structures indicate that some other major tectonic process has operated (and presently continues) in this region of the New Britain arc to create these structures. 相似文献
835.
836.
土地利用信息的多元分析提取 总被引:1,自引:0,他引:1
由遥感(RS)、地理信息系统(GIS)和全球定位系统(GPS)获取、处理、分析空间信息,已成为研究资源环境的重要技术手段。在土地利用信息提取中,我们先后应用了传统目视解译方法、人机交互解译方法、计算机自动分类方法、多源信息复合分析等方法。本文在分析现有各种方法优缺点的基础上,提出了“综合自动分类方法”,并以北京市密云县为例,对土地利用信息进行了提取。分析表明:综合自动分类方法在分类结果的客观性、科学性、实用性等方面,具有一定的优势。 相似文献
837.
地震预报科学发展需要新思维和新的观测手段 总被引:2,自引:0,他引:2
通过对地震预报现状的分析,认为传统的地震预报思路仍是目前经验性地震预报所依托的。但是要想从质上提高地震预报水平,使地震预报水平上一个大的台阶,必须引入新的思维和新的观测手段。新思维常常产生于新的观测结果中和隐含于失败的地震预报教训中。地震科学是一门依赖于观测的科学,新的观测手段和新的研究思路在地震预报的科学发展中将起到重要的或决定性的作用。 相似文献
838.
The Schmidt hammer (SH) is widely used in geomorphology for relative- and calibrated-exposure age dating surfaces and deposits within landforms. This study employs a laboratory-based methodology to assess the effects of surface roughness, clast roundness, and clast volume on SH rebound values (R-values) by analyzing samples from three modern depositional environments (i.e. river, alluvial fan, talus). Each environment contains clasts of Torlesse supergroup greywacke sandstones with distinct roundness and micro-scale roughness characteristics. Roundness, surface roughness, and clast volume were all found to influence R-values significantly. The R-values from different deposit types are statistically significant and could potentially create an apparent age divergence of several thousand years for samples with the same exposure-age. © 2020 John Wiley & Sons, Ltd. 相似文献
839.
Soil moisture is an important variable in hydrological studies, but has been little used for model evaluation due to its high sensitivity to local conditions. We explore the possibility to derive hydrological signatures from soil moisture data that could overcome this limitation and be helpful for model evaluation. A set of eight hydrological signatures was built, encompassing long-term to short-term time scales. These signatures were tested according to robustness, representativeness and discriminatory power, using in situ data sets from New Zealand, including national network and experimental watershed data. Field capacity, type of soil moisture distribution, and starting dates of seasonal transitions typically meet the criteria, subject to uniform sensor depths and homogeneous land uses. Durations of seasonal transitions and event-based signatures showed higher variability and lower discriminatory power. In general, long-term signatures are more robust, more representative of large areas, and have a high discriminatory power, thus showing a good potential for use in diagnostic evaluation of regional models. 相似文献
840.
The Devonian mafic rocks from the Folly Basalt, northeast New South Wales, were emplaced in the forearc section of the Devonian‐Carboniferous magmatic arc preserved in the western part of the New England Fold Belt. Trace‐element abundances in fractionated metadolerites (maximum concentration of Ni = 85 ppm) from the Folly Basalt outcropping near Nundle demonstrate that these rocks have MORB affinity. Chondrite‐normalised rare‐earth element patterns are smooth and quasi‐horizontal; Ce/Yb ratios are 3.34–7.98; (La/Yb)N ratios range from 0.69 to 2.23; (La/Sm)N ratios of the rocks range from 0.63 to 1.55. The data are compatible with an origin of the melts from large degrees (>15%) of partial melting of mantle peridotite. A plausible mechanism for the production and emplacement of depleted magmas in the forearc zone of the Middle Palaeozoic eastern Australian magmatic arc involves the subduction of a hot oceanic spreading centre, which could cause the presence of a region of asthenospheric temperatures below the upper plate. It is also suggested that sustained high‐temperature conditions may have prevailed in the eastern Australian mantle for at least the last 400 million years. 相似文献