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61.
层析SAR反演森林垂直结构参数现状及发展趋势 总被引:2,自引:1,他引:1
森林垂直结构参数反演是进行森林资源管理、森林蓄积量估算及全球碳循环研究的基础。层析合成孔径雷达TomoSAR(Tomography Synthetic Aperture Radar)是随着InSAR/Pol-InSAR技术的日益发展而产生的,更适用于森林垂直结构参数反演。本文首先介绍了TomoSAR的概念与实现方式:PCT(Polarization Coherence Tomography)、多基线干涉层析SAR MB-InTomoSAR(Multi-baseline Interferometric Tomographic SAR)、多基线极化层析SAR MBPolTomoSAR(Multi-baseline Polarization Tomographic SAR);概括了目前应用TomoSAR技术反演森林垂直结构参数的技术方法与信号模型等;论述了应用TomoSAR技术提取森林垂直结构参数的现状,最后分析了应用TomoSAR技术提取森林垂直结构参数可能的发展方向。 相似文献
62.
S. Vinciguerra C. Trovato P.G. Meredith P.M. Benson C. Troise G. De Natale 《Pure and Applied Geophysics》2006,163(10):2205-2221
We report laboratory measurements of P- and S-wave velocities on samples of tuff from Campi Flegrei (Italy), and a new tomographic
velocity map of the Campi Flegrei caldera. Laboratory measurements were made in a hydrostatic pressure vessel during both
increasing and decreasing effective pressure cycles. Selected samples were also thermally stressed at temperatures up to 600°C
to induce thermal crack damage. Acoustic emission output was recorded throughout each thermal stressing experiment, and velocities
were measured after thermal stressing. Laboratory P- and S-wave velocities are initially low for the tuff, which has an initial
porosity of ~45%, but both increase by between 25 and 50% over the effective pressure range of 5 to 80 MPa, corresponding
to a decrease of porosity of ~70%. Marked velocity hysteresis, due to inelastic damage processes, is also observed in samples
subjected to a pressurization-depressurization cycle. Tomographic seismic velocity distributions obtained from field recordings
are in general agreement with the laboratory measurements. Integration of the laboratory ultrasonic and seismic tomography
data indicates that the tuffs of the Campi Flegrei caldera can be water or gas saturated, and shows that inelastic pore collapse
and cracking produced by mechanical and thermal stress can significantly change the velocity properties of Campi Flegrei tuffs
at depth. These changes need to be taken into account in accurately interpreting the crustal structure from tomographic data. 相似文献
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A dynamical tomography method, which inverts dynamical indicators to evaluate the parameters controlling geological processes as well as those in intrinsic equations of state, was introduced into a 2D fluid flow/compaction model termed GEOPETII (developed at the University of South Carolina), with the assumption of invariance to spatial location of parameters in equations of state, but allowing geologic process parameters to change with well location. Synthetic tests, including sensitivity analysis, are given to illustrate the operation of the system. The nonlinear inverse two-dimensional tomography method, together with a systematic linear search procedure, provides a useful approach to determine and constrain the parameters entering quantitative models of dynamical sedimentary evolution. Applying the method to an interpreted section from a seismic line in the Navarin Basin. Bering Sea. Alaska, the predictions of present-day formation thicknesses, porosity, and fluid pressure with depth are improved at four controlling well locations (Amoco Mishu No. 1, Exxon Redwood 1, Exxon Redwood 2, and Amoco Danielle), relative to previous results which used only a forward model. In this way the geohistory and structural development of the basin can be defined better, which helps in the reconstruction of thermal history, and so of hydrocarbon generation, migration, and accumulation histories in relation to structural and stratigraphic development. 相似文献
65.
DST-3型井间声波探测和井中声波采油系统在冀东油田的试验 总被引:1,自引:0,他引:1
我们研制的DST-3型井间声波探测和井中声波来油系统,用于油气田井间层析成像,分辨率高、可检测度高;用于油层井中震动来油,功率大、作用范围大.该系统在冀东油田投入高104-5井和高105-5井试验,取得了210m井间距、1854.1m-1890m深部油层上较高质量的井间数据,经CT处理,获得了井间声波层析成像剖面.高104-5井1867.6m-1884.8m含油层经过13个小时井下声源震动解堵,这口原已不出油停产的井竟然出现原油自溢流出井口,后下泵抽油恢复产能.试验效果证实了系统的可靠性和实用性,显示该系统将会在油气田开发和开采中发挥特殊作用. 相似文献
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68.
中朝地台东北缘3km深度地震层析成像的地质解释 总被引:1,自引:0,他引:1
利用本区丰富的地质,人工地震探测资料,对3km深度层析成象成果进行了分析对比,结果表明:(1)3Km深度速度值与人工地震探测所获地震波速值吻合较好;(2)3km深度速度分布与该深度处的岩石介质分布有较好的对应关系,高速区对应地层主要为太古界-下元古界变质岩和地槽区的古生界浅变质岩,低速区对应主要为中生界火山,碎屑岩,燕山期花岗岩体和盖层性质的中元古-古代界沉积岩。(3)层析成象结果可划分深度不同的 相似文献
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70.
ZHENG Hongwei LI Tingdong HE Rizheng YU Haiying YANG Hui WEN Yanlin WANG Peng LIU Fang SUN Dongjun 《《地质学报》英文版》2022,96(2):621-630
The 3D P-wave velocity structure beneath the South China Block was determined by applying arrival times from 269 teleseismic events recorded by 240 seismic stations within the study region. Our tomographic results reveal the deep structural characteristics of major tectonic units and ore concentration areas. There are distinct high velocity anomalies beneath the ancient Yangtze and Cathaysia blocks, with the lithosphere of the Cathaysia Block being thinner than the Yangtze Block; the Jiangnan orogenic belt, located in the combined zone of two blocks, is a high and low velocity anomaly conversion zone; the famous metallogenic belts of Edongnan, the Youjiang Basin and the Cathaysia Block are obviously low velocity areas with different metallogenic mechanisms. The deep ore-forming material source in the Edongnan metallogenic belt is different from that of the Cathaysia Block. The low velocity anomaly under the Cathaysia Block related to mineralization results from the upwelling of mantle material, caused by the joint action of the Paleo-Tethys tectonic domain, the Paleo-Pacific tectonic domain and the Hainan mantle plume migration and erosion, which has been occurring from northeast to southwest since 80 Ma. The low-temperature mineralization mechanism of Youjiang Basin should be considered not only in terms of the influence of the Emeishan mantle plume in the west and the Paleo-Tethys tectonic domain in the south, but also in the context of the influence of the upwelling of asthenospheric material from the Paleo-Pacific tectonic domain in the east. 相似文献