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郭万武  李龙海 《地震研究》1995,18(2):213-220
本文根据地球物理,地震学资料及区域构造应力场的分布,研究了1990年4月26日发生了7.0级地震的共和盆地邻近地区的隐伏构造,本文提出,在微观上该地震由沿震源区存在的东西向断裂的左旋剪切运动所引起;在宏观上则由区域性东西几构造的端部破裂所产生,同时,研究结果也表明深部发震构造并不与地表构造特征一致。  相似文献   

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简述了近年来国内外在青藏高原晚新生代构造和第四纪地质研究方面所取得的新进展,针对在活动构造研究中所存在的问题,提出 今后研究工作的方向,认为应当加强青藏高原及其周缘地区晚新生代构造变形方式、幅度和速率的研究,同时在研究中应当将第四纪地质与活动构造研究相结合,特别要注重深部构造的研究。  相似文献   

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在欢庆中国地质学会成立60周年之际,马杏垣、索书田、游振东和刘如琦所著《嵩山构造变形》一书已由地质出版社出版,这本专著约38万字,附有大量插图和照片。全书共分四章,论述了嵩山的重力构造与构造解析。 《嵩山构造变形》一书是二十多年来由马杏垣教授亲自带领北京、武汉地质学院近百名师生长期野外观察与室内研究的集体劳动成果。为我国构造地质学现代化提供了重要的方法和理论。我国地质界老前辈中国地质学会理事长黄汲清教授认为该书“描述精细、讨论深入,特别对重力滑动构造之阐述令人信服,确是我国地质界之重大贡献,值得我们详细阅读”。同时,国际地科联构造委员会主席Zwart教授称赞该书是“对构造分析具有现代化的研究方法  相似文献   

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张治洮 《地震研究》1989,12(2):103-114
南北地震带是以青藏高原地壳为主体和兼并了扬子地块西部而成的新生构造实体,具弥漫性边界。构成其基本格架的巨型反S形或缓弧形构造带,分布在中部的弧顶朝南的弧形构造以及发育在东界附近的旋卷构造,成为南北地震带的三大构造特色,它们都是塑性伸展流动的产物。据弧形构造形态实际数据分析表明,地壳物质向南移动的规模,由北往南逐渐加大,从西到东渐逐减小;自北纬31.5°往南,青藏高原物质东移量逐渐加大。  相似文献   

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构造应力场地质研究方法进展   总被引:1,自引:0,他引:1  
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地震危险区划分的活动构造依据   总被引:1,自引:1,他引:1  
高维明  马集遐 《地震》1996,16(2):105-113
分析了地震预报方法与活动构造结合的现状,活动构造与地震危险区预测的内在联系。指出现今预报方法存在的问题以及与活动构造结合的必要。同时还研究了以地震构造带为代表的活动构造条件,对中国大陆地震密集带进行进行了统计分析。  相似文献   

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辽河裂谷的深部构造与裂谷活动的侧向迁移   总被引:9,自引:1,他引:8       下载免费PDF全文
赵俊猛  卢造勋 《地震地质》1998,20(3):34-233
对横穿辽河裂谷的闾阳-海城-东沟剖面的深部地震探测、重力测量、大地电磁测深、大地热流测量资料做了进一步分析,发现辽河裂谷地带壳幔间具有多个薄层过渡的特征,与东西两侧的辽东台隆和燕山台褶带明显不同。壳幔过渡带的薄层结构、速度结构、温度结构以及壳内低速层和软流圈顶面构造特点表明辽河裂谷的构造演化过程自西向东侧向迁移,当前上地幔物质运动的前锋不在裂谷之下,而是向东移至金州地震带附近的析木一带,深部物质运动是辽河裂谷形成及其活动性侧向迁移的主要动力学因素  相似文献   

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The determination of the coefficient of viscosity of eruptive products gives useful elements to the knowledge of possible variations of composition and physical conditions of the magmas.  相似文献   

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Until recently, the existing data prevented the geophysicists from accurately dating the Bysy-Yuryakh stratum, which outcrops in the middle reach of the Kotuy River, constraining the time of its formation to a wide interval from the end of the Late Cambrian to the beginning of the Silurian. The obtained paleomagnetic data unambiguously correlate the Bysy-Yuryakh stratum to the Nyaian regional stage and constrain its formation, at least a considerable part of it, by the Tremadocian. This result perfectly agrees with the data on the Bysy-Yuryakh conodonts studied in this work and yields a spectacular example of the successful application of paleomagnetic studies in solving important tasks of stratigraphy and, correspondingly, petroleum geology. Within the Bysy-Yuryakh stratum, we revealed a large normal-polarity interval corresponding to the long (>1 Ma) period when the geomagnetic reversals were absent. This result, in combination with the data for the Tremadocian and Middle–Upper Cambrian sequences of the other regions, indicates that (1) the rate of occurrence of the geomagnetic reversals on the eve of the Ordovician Moyero superchron of reversed polarity was at most one reversal per Ma; (2) the superchron does not switch on instantaneously but is preceded by a certain gradual change in the operation conditions of the dynamo mechanism which, inter alia, manifests itself by the reduction of the frequency of geomagnetic reversals with the approach of the superchron. This finding supports the views according to which a process preparing the establishment of the superchrons takes place at the core–mantle boundary.  相似文献   

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Geomagnetism and Aeronomy - The magnetic evolution of the active region of the Sun at the level of the photosphere has been studied. Magnetic synoptic maps of the 2007 Kitt Peak Observatory were...  相似文献   

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Резюме Дается вывод формул для вычислений длины хорды, длины и азимутов нормаляных сечений и длины геодезической линии эллипсоида. Применяются тригонометрические функции данных величин и постоянные принятого ргфгргнц-эллипсоида, что является целесообразным при использовании вычислителQjных машин, особенно автоматов. Рабочие формулы рекомендуются в форме (8–11).

Dedicated to Professor František Fiala on His 85th Birthday

Address: Veveři 95, Brno.  相似文献   

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Summary The author mentions the aims of the World-wide gravity project he established in the Ohio State University in Columbus, in 1950. He outlines the practical procedure of the gravimetric computations of the undulationsN and the vertical deflection components and and emphasizes that only by the global international cooperation and additional gravity observations at sea carried out during the last decade it has been possible to gather to Columbus the needed gravity material. Since there exist still large gravimetrically unsurveyed areas it is of vital significance to study what gravity anomalies are best to be used for these regions. The given figures concerning the accuracy of theN, and , estimated theoretically and obtained in practice, indicate that in the gravimetrically well surveyed parts of the world like in Europe and the United States we can get gravimetrically on basis of existing gravity material theN-values with accuracy of about 5–10 meters, and and with the accuracy of about 1. The geoid undulationsN are already computed in Columbus for more than 6000 points of the northern hemisphere. The sample maps show the interesting geoid of Europe and vicinity between the latitudes 60° and 30° and longitude 5° W and 30° E, drafted on basis of more than 1000N-values computed at the corners of 1°×1° squares. It is interesting to realize that the geoid undulations in all this area are positive, the extreme values being between 40 and 50 meters. The geophysical significance of the geoid maps of this kind is pointed out.  相似文献   

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Summary A simple model is proposed suitable for studying the effect of the ground layer of the atmosphere, polluted by aerosol, on the albedo. This model is founded on solving the equation of transfer of radiative energy. The numerical results are discussed, particular attention being paid to the analysis of errors due to neglecting the multiple reflection of solar radiation on the aerosol particles. A method which would also include the multiple reflection is proposed, and the conditions under which the presence of the aerosol is responsible for an increase or decrease of the solar radiation balance on the Earth's surface, are analysed.  相似文献   

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Summary The maintenance of the axisymmetric component of the flow in the atmosphere is investigated by means of a steady-state, quasi-geostrophic formulation of the meteorological equations. It is shown that the meridional variations in the time-averaged axisymmetric variables can be expressed as the sum of three contributions, one being due to the eddy heat transport, another to the eddy momentum transport, and a third to the convective-radiative equilibrium temperature which enters the problem through the specification of a Newtonian form of diabatic heating. The contributions by the large scale eddies are evaluated through the use of observed values for the eddy heat and momentum transports.The contributions from each of the three forcing mechanisms to the temperature and zonal wind fields are invstigated individually and found to be of about equal importance. The sum of the three contributions are also presented for the temperature, the zonal wind, the stream function associated with the mean meridional circulation and the corresponding vertical motion. Although the results fail to reproduce the main observed features of the lower stratosphere, they are found to be in good agreement with observations in the middle latitude troposphere. At any pressure level, for example, the computed mean zonal wind has a jet-like profile and the axis of the jet is found to slope to the south with height, as observed in the atmosphere.Based in part on a thesis submitted by the first author as partial fulfillment of the requirements for the Ph.D. degree at the University of Michigan. — Publication No. 194 from the Department of Meteorology and Oceanography, The University of Michigan.  相似文献   

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Summary The results of two different methods of the determination of the non-linearity of the gravimeter scale are compared; the economy is discussed as well.  相似文献   

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