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261.
A multi-functional high-frequency seismometer, a new instrumental system, is used for recording multi-point strain variations of rock samples in the process of fracture development. The results indicate that strain in each point appears burst disturbance synchronously besides a tendency variation before main fracture. The burst disturbance could probably be one of the short-impending precursors before great earthquake.  相似文献   
262.
前陆盆地类型及其沉积动力学研究综述   总被引:17,自引:2,他引:15  
从前陆盆地的特点及类型入手,综述了前陆盆地研究的热点内容,最新方法及其沉积动力学进展状况,揭示了前陆背景下盆地充填序列的构成及内部演化特征,指出了盆地的沉积-地层格架与冲断造山带的幕式活动之间的响应关系。  相似文献   
263.
The Ceshui Formation coal is mostly anthracite and its metamorphism has been less documented.By analyzing systematically the reflectance of vitrinite and the results of X-ray diffraction of the Ceshui Formation cola in the Lianyuan coal basin,the spatial variation characteristics of coal ranks,coal metamorphic regions,the extension of coal metamorphic belts.coal metamorphic gradients,coal chemical structure and the effect on the degree of metamorphism of heat-production and -storge conditions,buried depth of the Indosinian-Yenshanian granites at the margins of the Lianyuan coal basin are discussed.The research results in conjunction of the features of regional hydrothermal alterations,endogenetic deposits with the Ceshui Formation coal measures,and the development of secondary vesicles indicate that the telemagmatic metamorphism is the main factor leading to the metamorphism of the Ceshui Formation coal in the region studied.  相似文献   
264.
THREEKINDSOFTIMEDISTRIBUTIONFUNCTIONSOFREMARKABLEEARTHQUAKESINSEISMICSEQUENCESDiaoShouzhongWangHongweiChaoHongtaiHuaAijun(Sei...  相似文献   
265.
构造地球化学测量在找金中的应用   总被引:4,自引:0,他引:4  
通过马庄山地区构造地球化学测量找金试验和在特克斯县15号水系沉积物异常区开展构造地球化学测量的推广应用证明:构造地球化学测量工作,以遥感地质构造解译为先导,民裂裂构造裂隙充填物及蚀变岩石为采样介质,较岩石地球化学测量更具有矿直接性。  相似文献   
266.
本文根据1971-1998年福建台网地震资料,分析了台湾海峡南部与台湾东部区城中、强地震活动在时、空、强方面分布的相关性。  相似文献   
267.
本文通过叙述“11.26”地震谣传事件的形成及其在当地党委、政府有力指挥下,迅速予以平息,确保社会安定稳定。闸述了产生地震谣传事件的主要原因以及由此引发深思的若干问题:  相似文献   
268.
Extension of remote sensing of planetary bodies to the ultraviolet is now feasiable up to 2000 Å from earth-orbiting telescopes and spacecraft. The benefits of this extension is analysed on the basis of laboratory spectra taken on a large variety of terrestrial, lunar and meteoritic samples. Knowledge of the albedo for two wavelengths at 2300 and 6500 Å permits classification of a surface into one of the following types: lunar, carbonaceous chondrites, ordinary chondrites, achondrites or acidic rocks, basaltic rocks, irons. For lunar-type surfaces, a simple albedo measurement at 6500 Å can be converted into quantitative abundance determinations of silicate, aluminium oxide and iron; a large amount of telescopic lunar photometry data is available for mapping these abundances. Extension of the photometry to 2300 Å permits quantitative measurement of TiO2 abundances. For asteroids and non-icy satellites, rock-type classification and constraints in chemical abundances of Si, Al, Fe and Ti can be derived from photometry at 2300 and 6500 Å. The IUE telescope already orbiting the earth, the Space Telescope to come, the lunar polar orbiter and other spacecraft under prospect are potentially available to provide the photometric observations at 6500 and 2300 Å required.  相似文献   
269.
论民间法对中国少数民族地区环境法制建设的贡献   总被引:1,自引:0,他引:1  
创始于西方国家的环境法以工业化和民主政治为基础,在工业化程度不高、民主意识欠缺的少数民族地区开展环境法制建设必须尊重当地少数民族的自治权利及社会的法文化传统,发挥民间法对环境法制建设的贡献.因为民间法作为历史文化遗留有巨大的惯性力量,是实际存在于中国现代社会的有效秩序和规范来源.少数民族地区广泛存在的与环境保护相关的民间法能够成为地方环境立法的来源,帮助人们认同国家环境立法,并且弥补国家环境立法的空白,全面细致地规范人们开发利用环境的行为.  相似文献   
270.
In our previous study, we developed the Stokes–Darcy (SD) model was developed for flow in a karst aquifer with a conduit bedded in matrix, and the Beavers–Joseph (BJ) condition was used to describe the matrix–conduit interface. We also studied the mathematical well‐posedness of a coupled continuum pipe flow (CCPF) model as well as convergence rates of its finite element approximation. In this study, to compare the SD model with the CCPF model, we used numerical analyses to validate finite element discretisation methods for the two models. Using computational experiments, simulation codes implementing the finite element discretisations are then verified. Further model validation studies are based on the results of laboratory experiments. Comparing the results of computer simulations and experiments, we concluded that the SD model with the Beavers–Joseph interface condition is a valid model for conduit–matrix systems. On the other hand, the CCPF model with the value of the exchange parameter chosen within the range suggested in the literature perhaps does not result in good agreement with experimental observations. We then examined the sensitivity of the CCPF model with respect to the exchange parameter, concluding that, as has previously been noted, the model is highly sensitive for small values of the exchange parameter. However, for larger values, the model becomes less sensitive and, more important, also produces results that are in better agreement with experimental observations. This suggests that the CCPF model may also produce accurate simulation results, if one chooses larger values of the exchange parameter than those suggested in the literature. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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