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131.
本文以黄骅坳陷港西开发区为例,探讨在油田开发阶段,如何通过密井网区沉积微相定量几何学数据对新近系明化镇组沉积环境相似的稀井网区进行沉积微相三维建模的方法。密井网区研究表明,港西开发区河流相的单河道砂体宽度约50-300 m,一般为100-200 m,厚度约5-15 m,一般为6-10 m;漫溢砂体长、宽一般小于200 m;砂体结构主要为迷宫状和拼合板状两种型式。应用密井网区沉积微相定量几何学数据,采用标点过程方法,对井网较稀的目标研究区进行了三维沉积微相建模研究,并取得了良好的应用效果。  相似文献   
132.
Different scales of structural data reveal a complex deformation history of ultrahigh- pressure (UHP) rocks exposed in the Weihai-Rongcbeng area, NE Sulu (northern Jiangsu-eastern Shandong), eastern China. Excluding pre-UHP deformations, at least five major sequential deformational stages (D1-Ds) are recognized. The first deformation (DO produced a weak foliation and lineation in massive eclogites. The foliated eclogite with a dominant foliation containing a stretching and mineral lineation was developed during the I)2 deformation. Both the D1 and D2 deformations occurred under UHP metamorphic conditions, and are well preserved in the eclogite bodies. D3 structures which developed shortly after the formation of granulite/amphibolite facies symplectites are characterized by imbricated associations marked by a regional, steeply dipping foliation, compositional layering, eclogite boudinage, isoclinal folds and reverse ductile shear zones. The D3 deformation was accompanied by decompressional partial melting. A regional, gently dipping amphibolite facies foliation and stretching lineation, low-angle detachments, and dome- and arc-shaped structures formed during the D4 deformation stage dominate to some degree the map pattern of the Weihai-Rongcbeng UHP domain. The last stage of deformation (Ds) gave rise to the final exhumation of the UHP rocks. Ds is characterized by development of brittle-dominated high-angle faulting associated with emplacement of large volmnes of undeformed granite plutons and dykes dated at 134-100 Ma. The deformational and metamorphic sequence followed by the UHP rocks in the Weihai-Rongcheng area is similar to that studied in the entire Dabie-Sulu UHP and HP metamorphic belts from microscopic to mapping scale. Based on structural data, combined with available petrographic, metamorphic and geochronological data, a speculative tectonic evolutionary model for the Dabie-Sulu UHP and IIP belts is proposed, involving continental subduction/collision between the Sino-Korean and Yangtze cratons and subsequent polyphase exhumation histories of the UHP and IIP metamorphic rocks.  相似文献   
133.
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   
134.
~~Experimental remolding on the caprock’s 3D strain field of the Indosinian-Yanshanian epoch in Tongling deposit concentrating area1.Chang,Y.F.,Liu,X.P.,Wu,Y.C,The Cu,Fe Metallogenic Belt in the Middle-Lower Reaches of Yangtze River(in Chinese with English abstract),Beijing:Geological Publishing House,1991,1-379. 2.Yin,H.F.,Wu,S.B.,Du,Y.S.,South China is the part of multi-islands and multi-oceans system of Tethys,Earth Sciences(in Chinese),1999,24(1):1-12. 3.Wu,G G,Zha…  相似文献   
135.
工准噶尔库布苏金矿床岩脉与金矿成因关系的研究   总被引:4,自引:2,他引:2  
高怀忠  孙华山 《岩石学报》2000,16(4):595-601
库布苏金矿床的三个金矿带均产于闪长玢岩和花岗闪长斑岩内。为了研究这些岩脉与金矿的成因关系,测定了含金石英脉中英流体包裹体均一温度、成分、盐度和H2O的氢氧同位素,分析了含英脉和相关脉岩及围岩的稀土元素及微量元素,发现石英流体包裹体属有较高的均一温度、低盐度、富CO2的还原性流体,其阳离子组合为Ca^2+〉Na^+〉K^+或Na^+〉K^+〉Mg^2+,阴离子组合属Cl^1〉SO4^2-〉F^-型,  相似文献   
136.
江苏六合新生代玄武岩中地幔捕虏体的硫化物相研究   总被引:13,自引:3,他引:10  
徐九华  储雪蕾 《岩石学报》2000,16(4):492-498
江苏六合一带碱性玄武岩中的出露有以尖晶石二辉橄榄岩为主的地幔捕虏体,这些地幔矿物中普遍有硫化物相出现:(1)被寄主矿物捕获的早期硫化物颗粒。(2)产于矿物晶粒边界或次生裂隙充填物,(3)硫化物包裹体,包括单相硫的包裹体、硫化物-玻璃两相熔体包裹体和CO/2-硫化物-玻璃(含硅酸盐子矿物)的多相包裹体,电子探针分析表明,硫化物包裹体比例隙中硫化物具有更高的相对Fe和S含量,较低的Ni含量。硫化物包裹  相似文献   
137.
广东长坑金银矿床成矿流体成分及来源探讨   总被引:9,自引:0,他引:9  
张文淮  吕万军 《岩石学报》2000,16(4):521-527
对广东长坑金银矿床流体包裹体的研究表明,该矿床矿石中流体包裹体种类较多,以富气态烃包裹体与盐水溶液包裹体为主,包裹体相对含量统计表明,富气态烃包裹体占包裹体总数的大多数,表明成矿流体为富含气态烃的水溶液。金、银矿石均一温度测定主要集中在160~260℃之间,单个包裹体的拉曼光谱分析结果证果,成矿充体成分与赋矿围岩有密切关系,成矿本主要为盆地富有机质的热流体。  相似文献   
138.
The Langdu skarn copper deposit in the Zhongdian area, Yunnan Province, China, has an average Cu grade of 6.49 %. The deposit is related to a porphyry intrusion(*216 Ma), which was emplaced in the Upper Triassic sedimentary rocks of the Tumugou and Qugasi Formations.At the Langdu skarn copper deposit, carbon and oxygen isotope ratios of fresh limestones(d18O = 3.0–5.6 % relative to V-SMOW; d13 C = 24.5–25.7 % relative to PDB)and partly altered limestones(d18O = 27–7.2 to-1.9 %;d13C = 11.8–15.2 %) indicated that the deposit was a typical marine carbonate source. Oxygen and carbon isotope values for calcites formed at different hydrothermal stages are-9.1 to 0.2 and 10.1–16.3 %, respectively. Moreover,the carbon–oxygen isotopic composition of an ore-forming fluid(d18O = 5.0–9.5 %, d13 C =-7.3 to-5.3 %) suggested the presence of magmatic water, which most likely came from the differentiation or melting of a homologous magma chamber. The deposition of Calcite I may arise from metasomatism in an open system with a progressively decreasing temperature.Later, the minerals chalcopyrite, pyrrhotite, quartz and Calcite II were precipitated due to immiscibility. Water–rock interaction could potentially be responsible for Calcite III precipitation in the post-ore stage.  相似文献   
139.
The Yitong(伊通) basin is a Late Mesozoic and Cenozoic continental sedimentary basin in Northeast China.On the basis of well tests and seismic data,we use the 2D modeling technique to rebuild the pressure evolution and hydrocarbon migration in the Moliqing(莫里青) fault depression of the Yitong basin.Based on the modeling results,four conclusions are drawn as follows.(1) The Eocene Shuangyang(双阳) Formation within the Moliqing fault depression had entirely undergone three epi-sodic cycles of pressure accumulation...  相似文献   
140.
In order to ensure safe drilling in deep water and marine gas hydrate bearing sediments,the needed characteristics of drilling fluid system were analyzed.Moreover,the effect of different agents on hydrate formation and the low-temperature rheology of designed polyalcohol drilling fluid were tested,respectively.The results show that clay can promote gas hydrate growth,while modified starch and polyalcohol can inhibit hydrate formation to some extent,and PVP K90 has a good performance on hydrate inhibition.Th...  相似文献   
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