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941.
Based on the deformation characteristics of the ductile shear zones in Sumdo (松多) Group, the quartz fabric by EBSD (electron backscatter diffraction), the data of muscovite 40Ar-39Ar geochronology (220-230 Ma) from ductile shear zones and the zircon SHRIMP U-Pb chronology (190 Ma) of granites in Snmdo region, Lhasa (拉萨) terrane is thought to have experienced an important Indosinian orogenic event at 220-230 Ma, which caused the closure of the paleo-Tethys Ocean along the tectonic zone of eclogite and the collision between northern part and southern part of the Lhasa terrane. The zircon SHRIMP U-Pb chronology of 190 Ma for biotite adamellite, with the distributing characteristics of the granite massif intruding in Sumdo Group, indicates that the biotite adamellitc should be the late orogenic or post-orogenic granite resulting from the lndosinian orogenesis. The discovery of Indosinian orogenic belt in Lhasa terrane expansed the southern boundary of lndosinian orogenic belt in Qinghai (青海)-Tibet plateau to Lhasa terrane from Qiangtang (羌塘) terrane, which changed the understanding about the distribution of Indosinian orogenic belt in Qinghai-Tibet plateau and extended the "T" type lndosinian orogenic belt in China. The study is very important for the formation and distribution of paleo-Tethys Ocean in Tibet. The ancient terrane framework and evolution of Qinghai-Tibet plateau need further research. 相似文献
942.
The multiquadric method (MQ) with high interpolation accuracy has been widely used for interpolating spatial data. However, MQ is an exact interpolation method, which is improper to interpolate noisy sampling data. Although the least squares MQ (LSMQ) has the ability to smooth out sampling errors, it is inherently not robust to outliers due to the least squares criterion in estimating the weights of sampling knots. In order to reduce the impact of outliers on the accuracy of digital elevation models (DEMs), a robust method of MQ (MQ-R) has been developed. MQ-R includes two independent procedures: knot selection and the solution of the system of linear equations. The two independent procedures were respectively achieved by the space-filling design and the least absolute deviation, both of which are very robust to outliers. Gaussian synthetic surface, which is subject to a series of errors with different distributions, was employed to compare the performance of MQ-R with that of LSMQ. Results indicate that LSMQ is seriously affected by outliers, whereas MQ-R performs well in resisting outliers, and can construct satisfactory surfaces even though the data are contaminated by severe outliers. A real-world example of DEM construction was employed to evaluate the robustness of MQ-R, LSMQ, and the classical interpolation methods including inverse distance weighting method, thin plate spline, and ANUDEM. Results showed that compared with the classical methods, MQ-R has the highest accuracy in terms of root mean square error. In conclusion, when sampling data is subject to outliers, MQ-R can be considered as an alternative method for DEM construction. 相似文献
943.
用转换波检测煤层裂隙的方法探讨 总被引:7,自引:2,他引:7
根据理论模型计算结果对比分析找出的煤层纵波场和转换波场和转换波场与煤层裂隙状态变化间的相关关系,探讨了综合使用纵波和转换波检测煤层裂隙的可行方法,对有效开展转换法地震勘探工作具有指导意义。 相似文献
944.
电偶源瞬变电磁测深研究(四)--瞬变电磁测深视电阻率 总被引:1,自引:0,他引:1
给出了由电偶源垂直磁场Hz(t)计算全区(期)视电阻率的数值计算方法;将时间范围扩展到几十秒,以满足大偏移距(r)探测大深度的需要。模拟计算结果显示,全区视电阻率能清晰地反映地电断面的结构,有助于定性定量解释 相似文献
945.
946.
Ju Weimin Fang Hongliang Tian Xiangjun Jiang Fei Zhan Wenfeng Liu Yang Wang Zhengxing He Jianfeng Wang Shaoqiang Peng Shushi Zhang Yongguang Zhou Yanlian Jia Binghao Yang Dongxu Fu Yu Li Rong Liu Jingxian Wang Haikun Li Guicai Chen Zhuoqi 《地球科学进展》2016,31(11):1105-1110
The Paris agreement signed in April, 2016 aims to balance global anthropogenic carbon emissions and terrestrial carbon sinks by the middle of the 21st century. To fulfill this goal, it is necessary to calculate carbon fluxes of different regions reliably. The global carbon assimilation system is an effective technique for achieving this goal. The Ministry of Science and Technology of China supports the project entitled as study on the global carbon assimilation system based on multisource remote sensing data through the national key research and development programs for global change and adaptation during the thirteen-five period. This project will develop synergic inversion techniques for retrieving key parameters of biological and atmospheric cycles and for assimilating multisource remote sensing and ground based data. Then, the high resolution global carbon assimilation system coupled with an ecological model will be constructed. This system is able to assimilate jointly multisource observation data and to optimize key model parameters, photosynthesis and respiration carbon fluxes of global terrestrial ecosystems, and anthropogenic carbon emission fluxes of key regions. This system will be used to study quantitatively the spatial and temporal patterns of carbon fluxes of global terrestrial ecosystems and anthropogenic carbon emission fluxes of key regions and to identify the mechanisms driving the global terrestrial carbon sinks and sources. The outputs of this study will be helpful for the fulfillment of the key research and development programs for global change and adaptation and provide valuable data and technical support for the decision-making in China. 相似文献
947.
Guor-Cheng Fang Chaur-Tsuen Lo Winn-Jung Huang Jyh-Cherng Chen Yuh-Shen Wu Jun-Han Huang Yi-Liang Huang 《Environmental Earth Sciences》2011,64(5):1237-1247
The main purpose of this study was to monitor ambient air particles and particulate-bound mercury Hg(p) in total suspended
particulates (TSP) concentration, dry deposition at five characteristic-sampling sites. In addition, the calculated/measured
dry deposition flux ratios of ambient air particles and particulate-bound mercury Hg(p) using three dry deposition models
during the years of 2009–2010 were also studied. The results showed that the order of seasonal variations for mean particulate-bound
mercury Hg(p) concentrations in TSP at Bei-shi (suburban/coastal), Chang-hua (downtown) and He-mei (residential) were all
shown as spring > fall, winter > summer, respectively. However, the order of seasonal variations mean particulate-bound mercury
Hg(p) concentrations in TSP that occurred at Gao-mei (wetland) were shown as spring > fall > winter > summer, respectively.
Finally, the results of this study also indicated that using the Noll and Fang model exhibited batten prediction results for
ambient air particles and particulate-bound mercury Hg(p) dry deposition when compared with the other depositions models at
any of the characteristic-sampling sites for this study. 相似文献
948.
ATLAS III in situ heating test in boom clay: Field data,observation and interpretation 总被引:1,自引:0,他引:1
The ATLAS III small scale in situ heating test aimed at assessing the thermo-hydro-mechanical (THM) effects on the Boom clay of the significant temperature gradients generated in this host rock as a consequence of the geological disposal of radioactive, heat-emitting wastes. This paper presents data on temperature, pore water pressure and total stress measured during the experiment and highlights several interesting observations regarding the thermal anisotropy and THM coupling in the Boom clay. The test has a simple geometry and well defined boundary conditions, which facilitates the comparison between measurement and numerical modeling studies. These studies included three dimensional coupled THM modeling of the test. The good agreement between measurement and numerical modeling of temperature and pore water pressure yields a set of THM parameters and confirms the thermo-mechanical anisotropy of the Boom clay. 相似文献
949.
近年轴流转桨式机组水电站进水口事故闸门有两种布置方式,一门一机布置和多门一机布置.本文结合轴流转桨式机组特性,阐述防止机组飞逸的保护措施.然后通过两种布置方式的优缺点比较,建议采用一门一机的方式. 相似文献
950.
为加强浙东南山区滑坡灾害防治工作,在分析该区山外高速滑坡和南充高速滑坡的物质结构和和运动特征的基础上,总结该区高速滑坡的形成原因、致灾原因和致灾方式.高陡原始地形伴随人工切坡,岩体超深风化,台风引起超强降雨.以及峰残强度降差形成滑坡;高速和远程是致灾的主要原因;致灾方式包括堆积掩理、抛洒冲击和气浪推掀. 相似文献