共查询到20条相似文献，搜索用时 234 毫秒
1.
The application of methods of modern theory of Brownian motion to the calculation of fluctuations of soil moisture reserve is considered. Analytical dependences of the correlation time of soil moisture reserve fluctuations and its mean on the characteristics of external stochastic and deterministic impacts are obtained for a nonlinear hydrological model of moisture reserve formation based on Langevin equation and generalized Langevin relationships. Variations of the low-frequency part of the spectrum of fast synoptic variables (the difference between precipitation and evaporation) because of interaction with moisture reserve fluctuations is examined. A new effect—an increase in the spectrum in the intermediate domain of time intervals between characteristic times—is explained by the time of variations of synoptic fluctuations and the time of variations of fluctuations of soil moisture reserve. The problem of determining a non-steady response of the mean soil moisture reserve to fluctuation of moistening regime is used to demonstrate the potentialities of a new apparatus of statistical physics-fluctuation theorems. 相似文献
2.
Yu. S. Bretshtein 《Izvestiya Physics of the Solid Earth》2009,45(6):495-507
In the present paper the new petro- and paleomagnetic data on the Jurassic terrigenous complexes of the Mesozoic sedimentary basins of the Amur River region, Trans Baikal region, and Yakutia are presented. The magnetic properties of the sedimentary rocks of coastal-marine (paleo-shelf) and lake genesis are investigated in the contemporary intracontinental riftogenic Mesozoic superimposed troughs of the Siberian and Amur plates: the Chulmansk, the Unda-Dainsk, the Sredne-Amur, the Amuro-Zeisk, and the Verkhne-Bureinsk troughs. The statistically significant differences in the magnetic (anisotropic) characteristics of continental and marine deposits were inferred. The correlation of the scalar and tensor characteristics of magnetic susceptibility anisotropy and the parameters of its linearity, which depend indirectly on the intensity of the folding, is established. The preferential directions of regional stress during the fold formation are determined based on the analysis of the distribution of the axes of the tensor ellipsoid of the magnetic susceptibility anisotropy. The Jurassic positions of the paleomagnetic pole, which are close to the Mesozoic section of the trajectory of its apparent motion for the North Chinese plate and which differ from the Jurassic poles of the Siberian plate, are defined more accurately. The intraplate rotations of geoblocks within the limits of the amalgamated to the end of the Jurassic-to the beginning of the Cretaceous terrains as a part of the Amur tectonic plate are inferred. The calculated coordinates of the paleomagnetic pole indicate the larger than the present-day difference of the latitudinal positions of the southern part of the Siberian plate, and also of the Amur and North Chinese plates in the Early-Middle Jurassic time. This can be indicative of the fact that the total width of the shallow residual basins of the Paleo-Asian Ocean, which separated the geoblocks indicated in the Early-Middle Jurassic, attained the first thousands of kilometers, and/or such a difference in the paleolatitudes reflects the total value of the shortening (crowding) of the crust during the accretion and the fold formation. The time of the completion of the accretion of the terrains of the Amur and the North-Chinese plates and their attachment to the Siberian plate is not earlier than the end of the Late Jurassic-the beginning of the Cretaceous. 相似文献
3.
4.
Summary Three important characteristics of the stochastic relation between the position of one point of a geodetic network and the positions of the remaining points are investigated: a) Change of the ellipse of confidence of the position of a point of the network to the ellipse of confidence of the position of a point of the network, relative to any other point of the network. (This characteristic is called the change of the global ellipse of confidence to the relative ellipse). b) The regression between the positional vector of the investigated point and the positional vectors of some group of other points of the network and c) the so-called total correlation between any two points of the network. The latter characteristic is a question of determining a characteristic direction for each pair of investigated points, which would have the property that the correlation coefficient between the random displacement of the first point in its characteristic direction and the random displacement of the second point in its characteristic direction is maximum. 相似文献
5.
We study temporal changes of the rigidity (R) spectrum of the harmonics of the 27-day variation of the galactic cosmic ray (GCR) intensity using neutron monitors (NM) data for the period 1965–2002. We show that the rigidity spectrum of the third harmonic (9 days) of the 27-day variation of the GCR intensity changes in a similar way as the spectra of the first and second harmonics, being hard in the maximum epochs and soft in the minimum epochs of solar activity. We ascribe this finding to the alternation of the sizes of the modulation regions of the 27-day variation of the GCR intensity in different epochs of solar activity. The average size of the vicinity of the corotating interaction regions, causing the 27-day variation of the GCR intensity, is less in the minimum epochs than in the maximum epochs of solar activity. A vicinity of the corotating interaction regions of larger size involves in modulation higher rigidity particles of GCR than the vicinity of smaller size; thus, this statement can be considered as one of the reasons leading to the hardening of the rigidity spectrum of the harmonics of the 27-day variation of the GCR intensity in maximum epochs compared with minimum epochs of solar activity.We also show that the temporal changes of the power rigidity spectrum of the third harmonic of the 27-day variation of the GCR intensity are negatively correlated with the rigidity spectrum of the 11-year variation of the galactic cosmic ray intensity.We found a recurrence in the temporal changes of the amplitudes of the first harmonic of the 27-day variation of the GCR intensity and in some parameters of solar activity and solar wind. 相似文献
6.
Summary The degree of astaticism is the fundamental parameter of an astatic magnetometer, an instrument used in geophysics for magnetic measurements of rock specimens. The degree of astaticism is formulated with a view to the vectorial character of the defining quantities and with a view to the effect of the geomagnetic field. As regards measuring the parameter, the mirror method is given, which makes use of the positive and negative orientation of the astatic system relative to the north or east. The measure of the value of the parameter is the change of the sensitivity of the system and the deflection of its zero position, compensated for by the magnetic field of the calibration coil. The problem of the degree of astaticism is treated complexly, inclusive of the measurement of the parameter, which in practice is of fundamental importance for adjusting the systems for manufacturing astatic magnetometers. 相似文献
7.
8.
本文利用两个频率通道同时接收花岗岩标本及石灰岩标本在不同单轴加压方式下的声发射信号,研究了从加压到破坏的整个形变过程中,不同频道接收到的声发射率的变化特征.发现在各种加压方式下,花岗岩和石灰岩在破坏前,由不同频率通道接收到的声发射率均急剧增长;而在破坏的瞬间,高频通道接收的声发射率增长快于较低频率通道的声发射率.这两点可用来预测岩石的破坏.声发射率随轴向应力的变化与加压方式有关.匀速加压,加压过程中保持一段时间恒压或降压均对应一定的声发射率状态.有可能通过追踪声发射情况,推测应力变化趋势. 相似文献
9.
根据介质Q值理论,通过小震记录中地震直达波P波测定了山西断陷带北中部的介质Q值。从定襄、代县、灵丘、大同台的小震目录中精选出92个记录波形好的地震样本进行了Q值测定,弄清了山西断陷带北中部的介质Q值分布情况,得出了Q值相对较高的区和点,这为未来山西中强地震的预报提供了一个重要依据。 相似文献
10.
1977年5月12日宁河6.6级地震的震中烈度较之震级相当的其他地震的震中烈度明显地偏低。为了阐明这种现象,由P波初动半周期及振幅求得了该区不同时期内的品质因数（Q值）及小震震源参数,并重新校对了这次地震以及1976年11月15日宁河6.9级地震的宏观及微观参数。分析结果表明:这次地震震中烈度异常低是因为1976年11月15日6.9级地震后,该区介质的品质因数大幅度下降,同时这个地震的震源深度比6.9级地震的震源深度约深5公里。品质因数和震源深度的综合效应可导致震中烈度降低近一度。 相似文献
11.
应用重力资源估算东海冲绳海槽地壳厚度 总被引：2，自引：1，他引：2
利用东海地区的重力资源，并参考在该地区进行的地震测深结果，应用线性公式估算了研究区的地壳厚度，分析了研究区地壳结构特征，根据与中国东部地球物理场、地壳结构的对比，指出东海大陆架地区应是中国大陆的自然延伸，对冲绳海槽的地壳性质进行了探讨，指出冲绳海槽应该为东海大陆架的自然终结。 相似文献
12.
The results of a study of the macroseismic effects in the territory of Moscow of a remote deepfocus earthquake that occurred on May 24, 2013 in the Sea of Okhotsk are reported. On the surface of the earth and on the first floors of the buildings the seismic effect was not felt. The effect of the shock began to manifest itself at levels higher than the fifth floor of the buildings. The distribution of points on the map where the earthquake was felt is non-uniform. Points where tremor was felt do not appear to correspond with certain types of Quaternary deposits or with zones of different depth. There is also no significant correlation of the parts of the surface with high intensities of tremor and areas of ground-water flooding. Comparison between the surface manifestations of the seismic event and the tectonic features and deep structure of the metropolis was made. Based on the results of the implemented statistical estimation of distribution points where the earthquake was felt on the territory of the city it is visible that fault zones govern the largest number of points, while block structures characterize almost half of them. Thus, we can reasonably suggest a certain macroseismic increase of vibrations from earthquakes in the areas of large faults in the city. The study of deformations of the asphalt cover of walkways on the landslide-affected slope of Vorobyovy Hills showed that the tremor caused by the Okhotsk deep focus earthquake of May 24, 2013, caused the activation of a small landslide at all levels of the hillside. 相似文献
13.
Following a companion article, ground motion acceleration time historiesduring earthquakes can be described as realizations of non-stationarystochastic processes with evolutionary frequency content and instantaneousintensity. The parameters characterizing those processes can be handled asuncertain variables with probabilistic distributions that depend on themagnitude of each seismic event and the corresponding source-to-sitedistance. Accordingly, the generation of finite samples of artificial groundmotion acceleration time histories for earthquakes of given intensities isformulated as a two-stage Monte Carlo simulation process. The first stageincludes the simulation of samples of sets of the parameters of thestochastic process models of earthquake ground motion. The second stageincludes the simulation of the time histories themselves, given theparameters of the associated stochastic process model. In order to accountfor the dependence of the probability distribution of the latter parameterson magnitude and source-to-site distance, the joint conditional probabilitydistribution of these variables must be obtained for a given value of theground motion intensity. This is achieved by resorting to Bayes Theoremabout the probabilities of alternate assumptions.Two options for the conditional simulation of ground motion time historiesare presented. The more refined option makes use of all the informationabout the conditional distribution of magnitude and distance for thepurpose of simulating values of the statistical parameters of the groundmotion stochastic process models. The second option considers allprobabilities concentrated at the most likely combination of magnitude anddistance for each of the seismic sources that contribute significantly to theseismic hazard at the site of interest. 相似文献
14.
利用“专家系统”的思想对每一地震前兆异常事件进行了综合评估，以每一异常的最可能发震时间计算发震概率，利用各类地震前兆异常群体信息熵研究了系统熵值与地震场，源兆的关系，分析了１９７６年唐山７．８级地震前各类地震前兆异常的时空分布特征，然后以唐山为中心在空间上划分三个区，近区，中间区和远区，分别计算了三个区各类地震前兆异常信息熵的时间演化值，分析了震前这种信息熵的场，源兆特征，震中近区的信息熵值要比中 相似文献
15.
许家亮 《CT理论与应用研究》2001,10(2):24-26
目的：进一步提高对腹部实质性器官损伤的CT表现的认识水平，方法：56例经临床、手术证实的腹部外伤患者，男43例，女13例，年龄7－58岁，平均年龄23．2岁，全部行中上腹部CT平扫。结果：56例中，脾挫裂伤23例，脾包膜下血肿5例，脾内血肿4例；肝挫裂伤并包膜下血肿4例，肝内血肿3例：肝脾破裂并包膜下血肿5例，肾挫裂伤2例，肾包膜下血肿3例，肾内血肿3例，胰腺挫伤1例，肾上腺挫伤2例。结论：CT平均对腹部实质性器官的损伤有重要作用，肝实质局限性受压是包膜下血肿与腹腔积血的较为特征性征象。 相似文献
16.
The procedure of choosing the shape of Gaussian beams in order to minimize a given object function of a certain kind is proposed. The general form of the object function enables both the average square of the quadratic variation of the phase and the average square of the beamwidth to be minimized along the central ray. The error of the transformation of the Gaussian beams at the structural interfaces may also be taken into account. Most of the hitherto published suggestions of how to chose the shape of Gaussian beams are special cases of the described procedure. The aim of this paper is not to propose the object function to be minimized, but only to describe the minimization of a given object function. The minimization assumes the a priori known lengths of the central rays of the Gaussian beams (i.e. the lengths of the beams are not free parameters in the minimization procedure). 相似文献
17.
18.
V. Yu. Burmin 《Seismic Instruments》2013,49(1):36-39
A problem of optimal arrangement of points of observation on surfaces of cylindrical form is considered. An accurate solution of this problem for these systems of observations is obtained. The optimal ratio of a cylinder diameter to the length of its generatrix from the standpoint of the optimal design of the experiment is determined. 相似文献
19.
Karel Prikner Jaroslay Střeštík Karel Dobeš Reviewer M. Hvoždara 《Studia Geophysica et Geodaetica》1973,17(4):337-345
Summary Using the method of two-component spectral analysis of planar oscillation events by means of computer processing of A-t records, a series of about 100 samples of geomagnetic beating-type pulsations pc3 was treated. The quantitative data obtained on the internal structure of the pulsations (frequency spectra and polarization characteristics) were treated statistically. The pattern of the daily variations of the frequencies and amplitudes of the fundamental amplitude-dominating frequency components of the pulsations and the daily variations of the polarization characteristics of these components, the ellipticity of the polarization ellipses, the directions of the main axes of these ellipses and the sense of rotation of the disturbance vector along the ellipses were obtained.A part of the results was reported at the XVth General Assembly of the IUGG, Moscow, August 1971. 相似文献
20.
G. N. Kopylova E. M. Gorbunova S. V. Boldina D. V. Pavlov 《Izvestiya Physics of the Solid Earth》2009,45(10):905-913
Statically isolated conditions in the stratum-borehole hydrogeological system under consideration at periods of ≥ 3 h are
established on the basis of the investigation of barometric and tidal responses of the water level in a borehole located in
the territory of the Mikhnevo Geophysical Observatory, Institute of Geosphere Dynamics, Russian Academy of Sciences. The barometric
effectiveness, tidal sensitivity of the water level, elastic parameters, and porosity of water-bearing rocks are estimated.
A model of the inertial character of the water exchange in the stratum-borehole system is constructed depending on the period
of variations with allowance for the borehole design, as well as the water transmissibility and elastic capacity of the aquifer.
The results of modeling are in compliance with the dependence of the amplitude transfer function from variations in the atmospheric
pressure to variations in the water level. The results of processing the data of high-precision measurements made it possible
to refine the transmissibility of the aquifer obtained from the data of experimental filtration works. 相似文献