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811.
Genetic Relationship between Natural Gas Dispersal Zone and Uranium Accumulation in the Northern Ordos Basin, China 下载免费PDF全文
The Ordos Basin is well-known for the coexistence of oil, natural gas, coal and uranium. However, there has been little research to discuss the genetic relationship between them. In this paper, a case study of the Zaohuohao area in Dongsheng, Inner Mongolia, China, is conducted to investigate the genetic relationship between the natural gas and the uranium accumulation. Fluid inclusion data from the uranium-bearing sandstone samples indicate that the fluid inclusions formed in a gas-water transition zone. Using the homogeneous temperatures of aqueous inclusions coeval with hydrocarbon-bearing inclusions, combined with the buried history and paleo-temperature data, the gas-water transition zone reached the area at about 110 Ma. On the basis of this, the contents of Uranium (U) and Total Organic Carbon (TOC) of the samples were analyzed, and there was no obvious relation between them. With regard to the available data from both publications and this study, it is found that the U mineralization has a spatiotemporal accordance with the gas-water dispersal zone. Thus, it is believed that the natural gas in the gas-water zone is an effective reducer to the U-bearing ground water abundant in oxygen, which is the main factor to U accumulation. This result can be used as the reference to the U mines predicting and prospecting. 相似文献
812.
813.
This study concerns the correlation between burden and blast-induced vibrations in open-pit mines. For this purpose, two different
mines were studied. In these mines, the vibrations caused by explosions at burdens having widths ranging from 3 to 14 m were
measured from various distances. From the results, it was found for these cases that burden width has a significant impact
on vibrations. Consequently, it was proven that vibrations decrease as burden increases. 相似文献
814.
徐州市矿山环境地质问题及防治对策 总被引:1,自引:0,他引:1
徐州市为我国著名的煤炭生产基地,是全国主要矿业城市之一。随着社会经济特别是矿业的不断发展,该市的矿山环境问题日益突出。如煤矿、铁矿地面塌陷破坏的土地21309hm2,开山采石占用与破坏土地1430hm2,造成矿区10万人失去了赖以生存的土地;矿坑排水、洗(选)煤水排放、煤矸石堆放、回填塌陷地及开山采石造成矿区水、土、气环境严重污染;井下采矿大量疏干排水造成水资源枯竭;采煤塌陷地破坏水利工程及道路等地表设施;开山采石影响自然景观及城市景观……。针对上述状况,文章从构建"绿色徐州"及"生态徐州"角度出发,提出一系列防治对策建议:①加快矿山环境保护与治理规划编制,严格矿山环境准入制度;②创建"绿色矿山",走可持续发展的道路;③重视采煤地面塌陷区的土地复垦,建设生态农业示范区;④加大废弃资源的综合利用,挖掘矿山旅游资源。 相似文献
815.
通过对火烧铺煤矿所处水文地质条件与矿井多年开采实测涌水量的分析与研究,总结出该煤矿矿井涌水量主要受开采面积、采空区面积和开采深度制约,其相关系数高达0.8以上,随着三者之一增加,矿井涌水量亦随之增加的规律性,为本区新建或改扩建的以裂隙充水为主的煤矿床提供了可比拟的依据。 相似文献
816.
矿山开采形成的采空区往往会给地表建筑物带来破坏,对采空区的治理方法也有多种,针对湖南某石膏矿采空区的分布与埋藏特征及其工程地质条件,采用了钻孔充填压浆法进行了治理。实践证明钻孔充填压浆法对采空区的治理具有成本低,设备简单,技术可靠,效果明显,有进一步推广的意义。 相似文献
817.
Intermediate sulfidation veins containing quartz–sphalerite–tetrahedrite–rhodochrosite–fluorite in the Sweet Home Mine, Alma
District, Colorado were originally mined for silver starting in 1873. For the last 13 years up until 2004, however, the mine
has produced world-class rhodochrosite specimens. Some of these specimens are considered to be among the finest mineral specimens
ever produced and the finest of their species with values well over $1 million US dollars. The extraction, preparation, and
marketing techniques pioneered at the Sweet Home operation have revolutionized the minerals specimen industry. The Sweet Home
deposit is interpreted as a single pulse variant of a Climax-type hydrothermal system. Evidence for this includes (1) an age
of mineralization (25.8 ± 0.3 Ma) that coincides with the age of the end stages of mineralization of the Climax molybdenum
deposit approximately 7.5 km to the northeast; (2) a geochemical (Mn, W, F) and mineralogical (topaz, fluorite, hubnerite,
greisen muscovite) signature typically associated with Climax-type systems; (3) the presence of porphyry rhyolite dikes, a
breccia dike, and local quartz–molybdenite veins in the nearby area; (4) a small pegmatite within the mine with an age (25.9 ± 0.3 Ma)
coincident with mineralization, which also contains minor amounts of disseminated molybdenite; and (5) the presence of similar-appearing
gemmy, red rhodochrosites at Climax and other high-silica rhyolite systems. A significant difference is that unlike Climax-type
systems, the Sweet Home hydrothermal system appears to have consisted of a single, relatively small pulse of magmatic fluid
that slowly cooled and diluted with groundwater. This is inferred to have occurred at moderate depths in the order of 1.5–2.5 km
below the surface. The fluids that formed the Sweet Home veins were dilute (salinity in the order of 2–4 wt% NaCl equivalent),
high-temperature (temperatures of homogenization up to 370°C), and initially of magmatic origin. Gem quality ruby-red rhodochrosite
at the Sweet Home Mine is nearly pure manganese carbonate with minimal solid solution with Fe+2, Ca, or Mg. It formed at higher temperatures and salinities in comparison to lower value, pink rhodochrosite. Gemmy, ruby-red
rhodochrosite is distinctly associated with highly evolved silica-rich igneous/hydrothermal systems. The high fluorine content
typical of such systems suggests that Mn was transported in solution as fluoride complexes, which, in turn, favored rhodochrosite
deposition at above-average temperatures and with minimal cation contamination.
An erratum to this article can be found at 相似文献
818.
为了降低成本、提高效率,国内的许多矿山企业正在开展"数字矿山"工程建设。与一般的企业不同,矿山的信息化需要地学专业软件的支持。本文分析了国内外矿山企业信息化的发展趋势,并列举了国外主要的矿山地矿软件和国内近年来出现的矿山软件。同时指出为了实现地矿软件的高效运转,需要对矿山的基础数据进行规范化整理,建立矿山地矿数据集成平台。为了得到更好的效果,需要将数据集成管理和矿山地矿软件中的功能处理结合起来,充分发挥两者的优势,为提高"数字矿山"的运行效率服务。 相似文献
819.
On 3D Geo-visualization of a Mine Surface Plant and Mine Roadway 总被引:1,自引:0,他引:1
WANG Yunjia FU Yongming FU Erjiang 《地球空间信息科学学报》2007,10(4):287-292
Constructing the 3D virtual scene of a coal mine is the objective requirement for modernizing and processing information on coal mining production. It is also the key technology to establish a "digital... 相似文献
820.
This paper investigates the dynamics of soil armouring as a result of fluvial erosion for a non‐cohesive sandy gravel spoil from the Ranger Mine, Australia, and a cohesive silt loam spoil from the Northparkes Mine, Australia, using a model for hillslope soil armouring. These long term predictions concentrate on the temporal and spatial changes of the spoil grading and erosion over 100–200 years for the flat cap regions (1–2%) and steep batter edges (10–30%) typically encountered on waste rock dumps. The existence of a significant rock fragment fraction in the Ranger spoil means that it armours readily, while Northparkes does not. For Ranger the waste rock showed reductions in (1) cumulative erosion of up to 81% from that obtained by extrapolating the initial erosion rate out 100 years and (2) the erosion/year by more than 10‐fold. For Northparkes reductions were less marked, with the maximum reduction in erosion/year being 37% after 200 years. For Ranger the reductions were greatest and fastest for intermediate gradient hillslopes. For the steepest hillslopes the armouring decreased because the flow shear stresses were large enough to mobilize all material in the armour layer. Model uncertainty was assessed with probabilistic confidence limits demonstrating that these erodibility reductions were statistically significant. A commonly used hillslope erosion model (sediment flux = β1 discharge m1 slope n1) was fitted to these predictions. The erodibility, β1, and m1 decreased with time, which was consistent with our physical intuition about armouring. At Ranger the parameter m1 asymptoted to 1·5–1·6 while at Northparkes it asymptoted to 1·2–1·3. At Ranger transient spatial trends in armouring led to a short term (50–200 years in the future) reduction in n1, to below zero under certain circumstances, recovering to an asymptote of about 0·5–1. At Northparkes n1 asymptoted to about 0·6, with no negative transients predicted. The m1 and n1 parameters predicted for Ranger were shown to be consistent with field data from a 10‐year‐old armoured hillslope and consistent with published relationships between erodibility and rock content for natural hillslopes. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献