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961.
轮古西奥陶系潜山洞穴型岩溶储层发育特征与充填规律   总被引:2,自引:0,他引:2  
洞穴型岩溶储层是塔里木盆地轮古油田缝洞型碳酸盐岩油藏的主要储集空间类型,多数高效井均钻遇大型洞穴型岩溶储层。依据轮古西奥陶系潜山大量单井资料分析,洞穴型岩溶储层可分为充填洞穴、半充填洞穴和未充填洞穴三种类型。结合古地貌精细刻画与岩溶垂向分带成果,认为古地貌位置由岩溶台地向岩溶缓坡和岩溶盆地逐渐降低,而洞穴发育和充填程度在逐渐增高。未充填与半充填洞穴主要发育在岩溶台地和岩溶缓坡的溶峰边坡、溶丘边坡及沟槽谷洼地边坡等地貌单元。表层岩溶带、径流溶蚀带洞穴型岩溶储层发育频率最高,其次为垂直渗滤带和潜流溶蚀带。未充填与半充填洞穴型岩溶储层主要发育在表层岩溶带。  相似文献   
962.
Many studies have been designed to assess seismic hazard and to improve post-earthquake damage evaluation models. Compared with previous studies, the research attempted to solve the problems of the effectiveness differences of seismic intensity on density of Earthquake-damaged trace (D e) and established the appropriate models for D e in different scale of seismic intensity. D e as a relative value reduced the influence of area on earthquake-damaged trace. The research will provide the necessary scientific support to fast post-earthquake damage assessment and modeling. By utilizing GIS, RS and field investigation data, the spatial distribution characteristic of earthquake-damaged traces was analyzed. Effective factors including seismic intensity, distance to rivers and slope were identified through PCA. Specifically, seismic intensity was identified as the key factor. The inherent relations between D e and seismic intensity, D e and distance to rivers in seismic intensity, and D e and slope in seismic intensity were modeled by regression analysis. The results demonstrated that both earthquake energy and D e have attenuation characteristics. There is a significant positive correlation between D e and seismic intensity (the pearson correlation is 0.917). That is, the higher the seismic intensity, the greater the D e was. The erosion of river leads to steep slope, which is in favor of the formation of mountain hazards. D e showed the decreasing tendency with the increasing distance to river. With the increase of slope, the D e gradually became stronger. For distance to river, the largest changing rate of D e appeared on seismic intensity XI, but for slope, the largest changing rate of D e appeared on seismic intensity X.  相似文献   
963.
964.
Partially due to lack of structural and sedimentary records to constrain the Jurassic-to-Cretaceous evolution, there was a missing process here in the eastern margin of Tibetan Plateau as it changed from the Paleo-Tethyan to Neo-Tethyan regime. Based on the analysis of 125 thermochronology ages (U/Pb, 40Ar/39A, 87Rb/86Sr, FT, U-Th/He) of igneous rocks from the eastern margin of Tibet, we propose a multisystem thermochronology approach to restore the cooling and emplacement of granites and decipher the missing process. Our integrated study suggests that a key Late Cretaceous (about 100Ma) tectonic change from the Paleo-Tethyan to Neo-Tethyan regime took place there. In the Late Triassic period, the initial emplacement of granite in the Songpan-Ganzi Fold Belt (SGFB) was characterized by a decrease in emplacement age and depth from west to east, and from north to south. Subsequently, all were followed by a very long period of slow cooling, which was followed by a rapid emplacement of about 100Ma. The intensive granite emplacement took place all over except northeastern SGFB, with a decrease in emplacement depth from west to east, which was linked with the far-field effect of Lhasa-Qiangtang collision. After this episode, the cooling history of granite in SGFB had a rapid emplacement on the subsurface under the control of the Neo-Tethyan regime. This process has control of the post Late Cretaceous regional magmatic activity and tectonics, as well as the sedimentary response in Sichuan and Xichang basin.  相似文献   
965.
《地面气象测报业务系统软件》(2004)开发至2012年已经修改多次并不断地完善,但编报过程中各个要素之间的相关检查的辅助提示功能不够完善,目前也没有相应的足够完善的外挂提示软件的推广应用,导致一些最基础的要素之间的检查都需要人工判断,如果不细心很容易导致错误。针对这个情况,下面将介绍能够检查编报过程中各个要素的外挂软件的开发过程(OSSMO V3.019)。  相似文献   
966.
对昆明地震台数字地震仪记录的2010年2月27日智利Ms8.8地震的震相进行分析,与格尔木、高台、呼和浩特、成都、银川、兰州、西妥等7个地震台记录进行对比,提出智利地震的记录特征、分析难点,并将JB表中Pdif波走时曲线的截止距离从150°延伸到177.8°。  相似文献   
967.
968.
The data-driven internal multiple elimination (IME) method based on feedback model, which includes CFP-based, surface-based and inversion- based methods, are successfully applied to marine datasets. However, these methods are computationally expensive and not always straightforward on land datasets. In this paper, we first proved that the surface-based IME method, which is the most computationally efficient method among the three methods, can be derived from the CFP theory. Then we extend it to CMP domain under the assumption of locally lateral invariance of the earth, which makes it more computationally efficient. In addition, we proposed applying a time-variant taper based on the first Fresnel zone to predict the multiples more percisely. Besides, the improved S/N ratio and dense offset distribution can be obtained by using the CMP supergather, which makes the CMP-oriented method more suitable for land data. Some practical processing strategies are proposed via case study. The effectiveness of the proposed method is demonstrated with the application to synthetic and field data.  相似文献   
969.
渭河盆地是我国乃至世界上地裂缝最发育、灾害最严重的地区。基于渭河盆地深部构造模式,采用有限元数值分析方法,分析了上地幔上隆、中地壳流展和上地壳拉张3种深部构造作用下盆地浅表岩土介质的应力和变形响应特征,从而揭示了渭河盆地深部构造活动与该区域地裂缝群发之间的孕育关系。结果表明:上地幔的隆起和中地壳侧向流展形成了浅部拉张应力环境,这种效应与盆地周边块体运动形成的伸展引张构造应力场叠加,再附加断裂伸展倾滑形成的局部拉伸应力场构成了地裂缝形成的主要动力来源。  相似文献   
970.
大巴山城口弧形断裂带右旋走滑构造特征及其意义   总被引:1,自引:0,他引:1  
大巴山弧形构造带是几何学上对称平顶型、内部形迹削截的弧凸结构带,区域走向总体呈北西向延伸,其主边界城口断裂由北向南发生偏转(由近南北向→北西向→近东西向),内部构造形迹与边界断裂呈明显削截和交切关系,弧形带凸顶方向与构造带南西向逆冲推覆极性一致。基于野外构造解析和15个样品的显微构造分析,对城口弧形断裂带右旋逆冲走滑构造特征和变形-变质特点及其沿走向的变化进行研究。宏观上,城口断裂带体现出早期近东西走向线理和平行于主断裂带弧形展布的后期线理两期世代和序列性,同时展现出强烈右旋走滑剪切变形特征,且走滑剪切变形强度由北西向南东减弱。微观构造上,断裂带构造岩普遍发生弱-中等强度变质,北段以中-高绿片岩相为主,右旋逆冲走滑剪切指向运动学标志体发育、变形强烈。断裂带南段以低绿片岩相为主,右旋走滑逆冲剪切指向运动学标志体相对稀疏、变形微弱。城口断裂带宏观与微观特征表明变质和(右旋走滑剪切)变形强度总体上由北西向南东逐渐减弱,呈非对称性。构造运动学上的非对称性和强烈右旋走滑剪切运动特征主要取决于印支期以来华南和华北板块汇聚过程中(尤其是燕山期)汉南能干性基底由南向北的强烈楔入作用。  相似文献   
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