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91.
92.
用流动形变观测判定强震危险地点的研究 总被引:1,自引:1,他引:0
分析了形变异常形成的机理,认为形变异常的空间与时间分布特征可以用断层活动闭锁区的形成及发展来解释,活动断层的闭锁区为强震发生地点。提出了半年至几年时间尺度判定强震危险地点的原则和判定危险区与危险地点的具体方法。 相似文献
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分析了目前利用流动形变、重力、地磁复测资料进行地震预测所存在的困难,探讨了综合利用三种手段追踪应力场及地下介质动态的途径,提出了断层综合监测布点的原则,并介绍了依此原则所建的京西试验场的基本情况。 相似文献
94.
Song Jingjing Xia Xiangao Zhang Xiaoling Che Huizheng Li Xiaojing 《Theoretical and Applied Climatology》2018,131(3-4):1019-1041
Theoretical and Applied Climatology - A weekly cycle of surface particulate matter (PM) characterized by smaller values during weekends and larger values during weekdays was reported in eastern... 相似文献
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湖南膨润土矿床成因类型及矿床实例 总被引:1,自引:0,他引:1
根据成矿地质条件及矿床特征,笔者将湖南省膨润土矿床归纳为四种成因类型:即滨海火山碎屑沉积矿床、内陆湖泊沉积矿床、浅海沉积矿床及风化残余矿床。文中对不同成因的矿床特征进行了简要介绍,并对湖南膨润土矿找矿标志进行了初步归纳。最后在全省范围内划分出六个找矿远景区,以期引起同行们的注意。 相似文献
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To study the characteristics of long period microtremor and applicability of microtremor survey,we have made microtremor observations using long period seismometers of the China's mainland from coastal cities like Shanghai and Tianjin through Beijing,Xi'an,to the far inland cities of Lanzhou and Tianshui.The observation shows that the level of power spectrum of long period microtremors reduced rapidly from the coast to the inland area.However,the energy of long period microtremors in Beijing,Xi'an,Lanzhou and Tianshui area are only approximately ten-thousandth to thousandth of that in Shanghai.Aiming at the complexity of the underground structure in the far inland,a series of underground structure models with different distributions were assessed using three-dimensional,dynamic finite element method(FEM) analyses.The results were used to evaluate microtremor survey methods and their limitations with regard to aggregate variability and thickness determinations.Multiple-wave reflections between layers with the change of underground structure distribution occurred,which have significant effect on the performance of the different field approaches.Information over a broad spectrum from which velocity-depth profiles were produced via inversion approaches.Neither the thickness nor the shear waveVelocity V of the subsurface layer inversion results appeared over a large evaluation with increasing slope angle.In particular,when the angle of the model reached 45°,it could not be accurately evaluated using one-dimensional inversion methods.Finally,the array microtremor survey(AMS) was carried out in Shanghai City,China.Although AMS techniques do not have the layer sensitivity or accuracy(velocity and layer thickness) of borehole techniques,the obtained shear wave velocity structure is especially useful for earthquake disaster prevention and seismic analysis. 相似文献
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Yanjun Che Mingjun Zhang Shengjie Wang Jie Wang Yangmin Liu Fuxian Zhang 《Arabian Journal of Geosciences》2016,9(19):732
The stable water isotope ratio in precipitation is a useful tracer of atmospheric circulation. Such observations, however, are very limited in space and time. To solve this problem, many isotope-enabled general circulation models (GCMs) are used to help the interpretation of isotope proxies. In this paper, several isotope-enabled GCMs released by the second Stable Water Isotope Intercomparison Group (SWING2) were selected to assess the spatial pattern of deuterium (δD) and the deuterium excess (d) of precipitation in China. The isotopic data of the Global Network of Isotopes in Precipitation (GNIP) and the Chinese Network of Isotopes in Precipitation (CHNIP) were also applied to verify the simulations. The results indicate that these models accurately simulate the spatial characteristics of δD and d of precipitation in China. The correlation between the observations and simulations for LMDZ is the highest among these models, while the root-mean-square (RMS) and standard deviation are not perfect. In addition, LMDZ is worse than other models in capturing the low signal in certain regions, such as CAM, GISS_E, and MIROC. For the monthly variation, most SWING2 models underestimate δD of the precipitation but overestimate the value of d, except for isoGSM. The simulated monthly variation of the water isotopes from SWING2 models is in general similar to the observations, and the trend corresponds to the monthly variation in the Northern Hemisphere. Moreover, all models are good at illustrating the temperature and precipitation amount effects, while they exhibit varying skills in interpreting the altitude and continental effects. 相似文献