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1.
美国的两位地震学家通过对记录到的数千次微小地震进行分析后 ,发现了一种跟踪加利福尼亚圣安德烈斯断层上微小地震的方法。当某个不知名的发震断层上的张力达到断裂点时 ,这种方法可以提供一些警报。据《科学》杂志 1 999年 7月 3 0日报导 ,两位地震学家共研究了在旧金山和洛杉矶之间的加州帕克菲尔德附近记录到的约 60 0 0次小地震。圣安德烈斯断层穿过帕克菲尔德的那段断层是世界上被研究得最充分的断层之一 ,因为该断层每隔数十年就会有规律地发生一次强烈地震。2 0世纪 80年代末期 ,加州大学伯克利分校的麦克埃维利 (Thomas V.Mc Evi… 相似文献
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旋转地震学涵盖了由地震、爆破和环境震动引起的旋转的所有方面。它作为研究前沿的出现由两篇专题论文和美国地震学会会刊（BSSA）的《旋转地震学与工程应用》专辑所说明。旋转地震学会使包括地震学、地震工程学和大地测量学各种分支的研究人员以及循爱因斯坦1916年的预测使用陆基观象台探测天文学源重力波的物理学家感兴趣。 相似文献
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2003年5月26日和7月26日在宫城县附近相继发生了宫城县近海地震(M7．0)和宫城县北部地震(M6．2)。地震学家们预测不久的将来在宫城县近海将会发生更大的地震(M7．5)。应该注意的是,从地震学的角度来看它们分属3种不同类型的地震。为了使非专业人员也容易理解,我将这3种不同类型的地震称之为“地震三兄弟”。这3兄弟,老大、老二在宫城县附近及其洋面上已和谐地出现,不久,老三也欲粉墨登场。 相似文献
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应用国家地震局 85 - 0 4 - 0 1课题提供的部分地震学预报地震方法对 1 980年和 1 981年博克图地震进行了研究。结果表明 ,该地震前后某些地震学预报项目出现了明显的异常变化。这些可作为监视该区地震活动的判定指标 相似文献
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20 0 2年 9月 8～ 1 3日中国地震学会第九次学术大会在青海省西宁市召开。会议期间 ,中国地震学会下属各专业委员会都召开了研讨会 ,现将有关专业委员会的研讨会概况汇编如下。1 地震学专业委员会研讨会本次讨论会上 ,研究人员展示了一批地震学前沿研究的高水平的最新成果。震源物理是研讨的重点问题。许力生报告了用长周期数字地震记录反演 2 0 0 1年 1 1月1 4日昆仑山 8 1级大地震震源的时空破裂过程的结果 ,给出了破裂过程的快照。分析结果表明 ,这次地震是由 3个扩展方向不同的破裂事件构成的复杂过程 ,由地震波反演的和由ＧＰＳ观测得… 相似文献
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亚洲地震委员会作为国际地震学与地球内部物理学协会(IASPEI)的地区性组织,自1996年在中国唐山成立以来,至今己成功举办过六届学术大会和五次地震学和防震减灾技术培训班,在推动和提高亚太地区的地震研究水平,增强各国防御地震灾害的能力,以及培养年轻人才等方面,都发挥了重要和积极的作用。目前,ASC已是IASPEI各委员会中工作最活跃的组织之一。2008年11月24—28日在日本筑波科学城召开,这次大会由亚洲地震委员会和日本地震学会共同主办,中国地震学会参与协办。大会研讨的主题是:共享现代科学和技术,减轻亚洲的地震灾害。欢迎中国地震… 相似文献
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阪神大震灾至今 ( 1月 1 7日 )整整 6周年了。去年 1 0月 ,日本西部地区发生了震级为7.3的鸟取县西部地震 ,人们再次感受到地震的恐惧。过去 ,四国至东海地区的近海一带一直有规律性地反复发生海沟型巨大地震 ,而在每次海沟型地震发生的前后其周边地区都频繁发生内陆型地震。部分地震学家认为 ,2 0 40年前后将要发生 M 8南海地震 ,在此之前 ,内陆地区将会不断发生大地震 ,尤其是日本海一侧很可能会连锁式地发生地震。大震发生后 ,日本西南部已进入地震活跃期。为确保人身安全 ,应提高警惕 ,常备不懈。南海地震“至下次南海地震之前 ,M 6.5… 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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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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Studia Geophysica et Geodaetica - 相似文献
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Josef Vykutil 《Studia Geophysica et Geodaetica》1968,12(2):217-220
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
Dedicated to Professor František Fiala on His 85th Birthday
Address: Veveři 95, Brno. 相似文献
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Prof. Dr. W. A. Heiskanen 《Pure and Applied Geophysics》1958,41(1):1-18
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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V. E. Pavlov T. Yu. Tolmacheva R. V. Veselovskiy A. V. Latyshev A. M. Fetisova I. V. Bigun 《Izvestiya Physics of the Solid Earth》2017,53(5):702-713
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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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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Ivanka Jakubcová Věra Marvanová Miloš Pick Antonín Novotný Reviewer Z. Šimon 《Studia Geophysica et Geodaetica》1982,26(2):193-196
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