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901.
Summary The magnification achieved with the standard sine-wave method using seismometers with the calibration and signal coils tightly wound on the same coil former can be erroneous at high frequencies due to the mutual inductance between both coils. An attempt was made to eliminate this influence from the calibration data. The application of theoretical equations was tested with a short-period digital seismograph.
ma¶rt;ama auau aa nu ¶rt;uu ¶rt;uu maauu m m m a u amma ua u a au u¶rt;mumu ¶rt; ua u auau am, u u a¶rt;m n¶rt;m umu. a ¶rt;aa nnma muam auau ¶rt;a. uu mmuu au u¶rt;a nu auauu mnu¶rt;u aa u anu.
  相似文献   
902.
Summary The paper deals with the computation of spherical harmonic coefficients from surface measurements of the magnetic or gravity field of the Earth when the measurements are distributed regularly. The Fourier representation of associated Legendre functions which this procedure makes use of, then enables the harmonic analysis to be transformed to Fourier analysis which has better numerical properties.
ama na ama uu uu uum n nm uu aum uuaumau n u a, ¶rt;a mu uu an ammu ma. ¶rt;mau n a¶rt; , m unm mm n¶rt;¶rt;, nm nmauu aau naam aau , m a¶rt;am uu uumu mau.
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903.
Summary The dependence of Pn-wave velocities on the heat flow, temperature at the crustmantle boundary and the thickness of the Earth's crust in Europe was investigated in relation to the problem of lateral inhomogeneities in the upper mantle. A map was constructed of the distribution of Pn-wave velocities on the territory of Europe. The relations these investigations yielded, were compared with the results of laboratory experiments and all the results are discussed from the physical point of view. The conclusion drawn is that that temperature and pressure effect provide a sufficient explanation of the observed regional changes of Pn-wave velocities for the European continent.
auum ¶rt;auu mu n¶rt; ¶rt; nmu uua (Pn) u mn nm, mnam a nmu amuu u m a mumuu n a u¶rt;aa u numa ¶rt;¶rt;m amuu. mumuu n a maa a uu m Pn- a nmu uua. u¶rt;u umam ¶rt;a mama aam u¶rt;au uuu m n¶rt; amuu u u ¶rt;au u mnam mmmm mama n¶rt;aa am. ¶rt;a ¶rt;, m ua uu m Pn- a n mum ¶rt;mam um uuu mnam u ¶rt;au a nmu uua.
  相似文献   
904.
Summary Tests on the vertical vibrating table in the frequency range of70–110 Hz indicate that quartz gravity meters are10–100 times more sensitive at some frequencies than under low-frequency excitation. At high frequencies, the reading beam is at rest and deflected from the correct position. Slow fluctuations of amplitude and frequency near resonance could cause slow irregular motion of the beam with absence of low-frequency ground motion of sufficient intensity.
unmauaum a mua um¶rt; ¶rt;uana amm 70–110u mam, m a m ammaaum 10–100 a mum nu uamm au. u amm au u a¶rt;um n m mu m nu. ¶rt; auauu anum¶rt; u amm au uu aa m am uamm u ua ¶rt;a mmmm uamm au n ¶rt;mam umumu.
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905.
<正> 在水文地质工程地质领域中,活动断裂以其对地下水的运移、富集及人类工程活动等方面的深刻影响而受到人们的重视。七十年代以来,随着我国地震工作的深入开展,区域水文地质工程地质普查的广泛进行,以及若干新的探测技术方法的引进,人们对活动断裂的区域分布规律、地质地貌特征及其水文地质工程地质意义等方面的认识日益深入。  相似文献   
906.
A detailed local structural map of the Mérens Fault zone at Port Vell (Vall Ferrera) reveals that the main fault-related mylonite band splits westwards into a network of mylonite zones. These consist of bands of highly-strained rocks exhibiting tightened folds, transposed foliations and extensive obliteration of pre-existing structures. Evidence of continuity of marble layers across the Port Vell mylonite zone, and structural and metamorphic similarities on both sides of the Port Vell mylonite band, indicate that there is no significant throw across it.The mylonite foliation forms parallel to the axial planes of tight folds in or near the mylonite zone which can be related to more open folds in adjacent areas. The Port Vell mylonite band corresponds to a pinched W-E axial trending late fold.In order to estimate the importance of these results, a review of the controversial geological significance of mylonite belts in the Pyrenees, with special emphasis on the Mérens Fault, introduces the paper.  相似文献   
907.
平面滑动标准化法是应用电子计算机处理(以下简体电算)大量区域水化资料的一种方法。它能够较好地反映水中各种元素的区域分布和圈定高背景区,准确地确定各类水异常的规模、强度和空间展布,有效地检出大量数据中的微弱信息,比传统整理方法具有显著的优越性。本文以65地区的应用效果加以说明。  相似文献   
908.
TL dating technique is of great advantage for determining the initial time of storing energy (T0) in an object to be analyzed. The sample is required to have undergone at least one thermal event, permitting all the residual storage to release. As a result, TL dating technique has found wide application in geochronology of pottery. The determination of T0 of loess is mainly based on the fact that fine particles of which loess is composed will lose their storage in the process of transportation by wind. In our experiment TL dating technique was adopted to determine the ages of fine quartz grains, and the results were corrected for those of shine-fading experiment. TL dating of Malan loess specimens from Mt. Gaolanshan, Liugouhe near Lanzhou, Mt. Qijiadashan in Jingning and Baichaoyuan in Huining gave the age values of 2.6±0.1, 3.6±0,3. 4.7±0.5 and 10.0±0.6×104 yr, respectively. The values indicate that the Malan loess began depositing in Late Pleisotocene, but the initial time and acumulation rate are different under different morphological conditions from place to place.  相似文献   
909.
新疆库布苏金矿石英标型特征研究   总被引:2,自引:0,他引:2       下载免费PDF全文
吕瑞英 《地球科学》1995,20(1):53-57
重点研究了库布苏矿化带中石英脉与金矿化关系,对不同成矿阶段石英的化学成分,晶胞参,红外光谱,热发光,包裹体等进行了研究,总结了找矿矿物学标志。  相似文献   
910.
东峰顶金矿某些成矿特征及其找矿意义   总被引:3,自引:0,他引:3       下载免费PDF全文
何文武  陆建培 《地球科学》1995,20(2):215-220
东峰顶金矿受断裂硫碎带控制,矿石中主要矿物成分有石英,黄铁矿,重晶石及褐铁矿,其标型特征具有成因和找矿意义,成矿流体为中低温、低盐度,弱酸性,低氧逸度和硫逸度,成矿物质主要来源于基底太古界变质岩系,表生作用使金的品位,成色获得大幅度提高。  相似文献   
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