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991.
准噶尔阜康东部斜坡区中侏罗统头屯河组高分辨
层序地层格架内储集层宏观非均质性研究 总被引:5,自引:0,他引:5
应用高分辨层序地层对准噶尔东部阜康东部斜坡区中侏罗统头屯河组进行层序的划分,共划分出1个长期基准面旋回、三个中期基准面旋回和10个短期基准面旋回。在中期层序地层格架下,按照层内非均质性、层间和平面三个级次对各层序进行非均质性剖析,发现储层宏观非均质性具有一定的规律性,主要在MSC2层序内表现明显。MSC2储集砂体的非均质程度最高,基准面上升初期及下降末期,储集砂体厚度较大,物性较好,是勘探开发有利区域。各层序的非均质性主要受到A/S值变化所影响。 相似文献
992.
993.
近年来,"两宽一高"——宽频带、宽方位和高密度——三维地震采集技术极大地提升了地震勘探的能力和精度,在岩性油气藏地区取得了明显的应用效果,也对地震采集观测系统设计提出了更高的要求.如何在现有的成本限制和装备条件下,根据具体工区的地质地球物理条件来选择合适的"两宽一高"采集观测参数以实现最佳的勘探效益,已成为当前地震勘探中迫切需要解决的瓶颈问题之一.基于此,本文首先回顾了点绕射聚焦分析的基本原理,随后给出一种新的复杂介质多频率快速聚焦分辨率定量分析方法.基于该理论,我们以一个典型的陆上三维地震勘探采集方案和速度模型为例,系统地研究了"两宽一高"地震资料偏移成像分辨率随着关键采集参数的变化规律,给出了不同条件下分辨率的理论极限值及其所对应的采集参数的临界点值.此外,我们也提出了一种新的采集参数和子波频谱的交汇定量分析方法,进一步阐明了采集参数和子波频谱参数之间的定量关系,为复杂接收激发条件下采集观测系统设计提供了新的理论依据. 相似文献
994.
高精度层序地层分析:建立沉积相和储层规模的等时地层格架 总被引:29,自引:13,他引:29
高精度层序地层分析以三级层序内高精度的层序地层单元的划分和对比为主要目的 ,它可为沉积体系的沉积构成和油气储、盖组合等研究提供精细的地层对比框架。从滨浅海至陆相湖盆的充填分析均表明 ,三级层序内可依据高频的海 (湖 )泛面或沉积基准面的变化划分出若干高精度的层序地层单元 ,包括四、五级层序以及低位、水进、高位及下降等 4个体系域。四级层序的识别和对比是建立高精度层序地层格架的关键。在煤、油气盆地中 ,四级层序是对储集体和聚煤作用进行分析的基本地层单元 相似文献
995.
A fast version of LASG/IAP climate system model and its 1000-year control integration 总被引:1,自引:1,他引:1
A fast version of the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geo- physical Fluid Dynamics(LASG)/Institute of Atmospheric Physics(IAP)climate system model is briefly documented.The fast coupled model employs a low resolution version of the atmospheric component Grid Atmospheric Model of IAP/LASG(GAMIL),with the other parts of the model,namely an oceanic component LASG/IAP Climate Ocean Model(LICOM),land component Common Land Model(CLM),and sea ice component from National Center for Atmospheric Research Community Climate System Model (NCAR CCSM2),as the same as in the standard version of LASG/IAP Flexible Global Ocean Atmosphere Land System model(FGOALS g).The parameterizations of physical and dynamical processes of the at- mospheric component in the fast version are identical to the standard version,although some parameter values are different.However,by virtue of reduced horizontal resolution and increased time-step of the most time-consuming atmospheric component,it runs faster by a factor of 3 and can serve as a useful tool for long- term and large-ensemble integrations.A 1000-year control simulation of the present-day climate has been completed without flux adjustments.The final 600 years of this simulation has virtually no trends in global mean sea surface temperatures and is recommended for internal variability studies.Several aspects of the control simulation’s mean climate and variability are evaluated against the observational or reanalysis data. The strengths and weaknesses of the control simulation are evaluated.The mean atmospheric circulation is well simulated,except in high latitudes.The Asian-Australian monsoonal meridional cell shows realistic features,however,an artificial rainfall center is located to the eastern periphery of the Tibetan Plateau persists throughout the year.The mean bias of SST resembles that of the standard version,appearing as a"double ITCZ"(Inter-Tropical Convergence Zone)associated with a westward extension of the equatorial eastern Pacific cold tongue.The sea ice extent is acceptable but has a higher concentration.The strength of Atlantic meridional overturning is 27.5 Sv.Evidence from the 600-year simulation suggests a modulation of internal variability on ENSO frequency,since both regular and irregular oscillations of ENSO are found during the different time periods of the long-term simulation. 相似文献
996.
997.
Modeling of dam-break flooding in an urban residential area in southern California is presented. Modeling is performed using BreZo, an unstructured grid, Godunov-type, finite volume model that solves the shallow-water equations. The model uses terrain data from a 1.5 m Light Detection and Ranging (LiDAR) Digital Terrain Model (DTM) and contour data depicting the reservoir and breach geometry. A spatially distributed Manning coefficient based on a landcover classification derived from digital orthophotos and vector data (e.g., parcel outlines) is also used, and the interception of flow by storm drains is modeled with sink terms in the 2D continuity equation. The model is validated with flood extent and stream flow measurements, and a sensitivity analysis is completed to identify the necessary level of data and model complexity for accuracy purposes. Results show street depressions in the land surface should be resolved by the computational mesh for flood extent and stream flow accuracy. A ca. 5 m resolution mesh that spans streets by approximately 3 cells achieves a good balance between accuracy and computational effort. Results also show that heterogeneous resistance is important for stream flow accuracy, and the interception of overland flow by storm sewers is important for flood extent accuracy. The sensitivity of predictions to several additional factors such as the reservoir level, breach geometry and DTM source (LiDAR, National Elevation Data, Shuttle Radar Topography Mission Data) is also reported. 相似文献
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1000.
This study presents results of a 2-D tomographic inversion of synthetic data that examines the ability of seismic tomography to reveal structures created by mantle dynamic processes. Our seismic velocity anomaly model is based on the density heterogeneities obtained from models of thermal and thermo-chemical convection. Both layered and whole-mantle models are employed to produce the synthetic input anomalies. We investigate the resolving power of the inversion of P and pP arrival times, and assess the influence of parameterisation and regularisation (damping). We show that the effect of regularisation is substantial and that the optimum damping depends upon the wavelength of the input structures. The resolution of the inversion decreases considerably at depths greater than 1000 km, therefore the ability of the kinematic inversion to distinguish between whole-mantle and layered flows (coupled via thermal coupling) may be limited. 相似文献