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1.
地球演化中表现出的最大两级节律为１０×１０８ａ和２×１０８ａ。每２个相邻节律可合并为一个周期，因而地球演化的最大两级周期为２０×１０８ａ和４×１０８ａ。岩石学、地层学和构造地质学方面诸多证据都说明这种划分的合理性。对于地球演化中的这类大型节律及周期性的成因机制，用笔者已提出的“地球多级驻波脉动理论模型”可以得到较合理的解释。 相似文献
2.
蒋志 《矿物岩石地球化学通报》2001,20(3):165-171
本文讨论了地球内部长寿期放射性同位素衰变能的存量 ,给出地球脉动频率和频数公式 ,并据以重新建立了理论地质年表 ,解释了地球自转变化、地磁场倒转和黄赤交角变化等。 相似文献
3.
Mortikov E. V. Glazunov A. V. Debolskiy A. V. Lykosov V. N. Zilitinkevich S. S. 《Doklady Earth Sciences》2019,489(2):1440-1443
Doklady Earth Sciences - We consider a relaxation equation for turbulence wavenumber in semi-empirical turbulence closures. It is shown that the well-known phenomenological equation for the... 相似文献
4.
Lin-Sen Li 《Astronomy Reports》2017,61(8):702-708
The differential equation and its solution for indirect influence of the planetary perturbation on the variation of the rotational angular velocity of the rigid Earth in the lunar-solar gravitational field are obtained by using Euler’s dynamic equations. The theoretical results show that the angular velocity of the Earth varies with the periodic and mixed periodic variation under the lunar and solar gravitational field due to the planetary perturbation on the Earth orbit. The numerical results for the amplitudes of the periodic terms and the coefficient of the mixed periodic terms are presented. 相似文献
5.
Doklady Earth Sciences - A probabilistic seismic hazard assessment is applied, for the first time in the case of Sakhalin Island, using a regional ground motion prediction equation in terms of the... 相似文献
6.
Models of the motion of the terrestrial reference frame with respect to an inertial frame can describe the motions of the Earth-Moon system, which are traditionally separated into precession, nutation, the polar motion, and rotation about the Earth’s axis. Existing theoretical models do not describe variations in the Earth-orientation parameters with the required accuracy, so that the current polar coordinates and duration of the day must be determined from observations. To improve theoretical models for the time dependence of the coordinates of the Earth’s pole, we examine the possible excitation of the Chandler wobble due to internal properties of the Earth-Moon system. A differential equation describing the parametric resonance in the Earth-Moon system is obtained for the first region of the parametric excitation. The solution of this equation analytically describes the finite amplitudes of the nonlinear conservative system. The theoretical results are compared with the empirical laws of Melchior deduced from observational data on the coordinates of the Earth’s pole. 相似文献
7.
时域瞬变场电磁场有限差分法 总被引：1，自引：2，他引：1
模拟电磁场在地下介质中的传播规律是理解地下介质响应的重要手段，直接应用有限差分法在时间域对二维、三维瞬变场进行数值分析是一种有效方法。应用反映电磁场基本规律的麦克斯韦方程组，导出时域场量的齐次扩散方程，对所研究的空间区域作差分离散，源作为初始条件加入，采用合适的边界条件，利用差分方程进行计算，从而得到场量的数值结果，展现瞬变场在地下随时间扩散的全过程，对电磁场的瞬态响应有更加直观的了解。 相似文献
8.
Chen Baoren Liu Shuyun Earth Sciences Dept. Nanjing University Nanjing Jiangsu China Jin Peikang Geological Dept. Tulane University New Orleans LA U.S.A. Dong Shouyu Hebei Province Seismological Bureau Shijiazhuang Hebei China 《《地质学报》英文版》1993,67(4)
The fluctuation of most of the hydrograph in the deep aqueous system records the fluid pulsation in lithosphere and variation of the earth's crust. Many observations have verified that groundwater is an ideal information carrier of the crust. In this paper, the series of input (precipitation, air pressure, Earth tide etc.) and output (water level, artesian flow) of the deep aqueous system are studied by using the spectrum analysis and system theory. The application concepts of transfer function and the spectral structure of the hydrograph enrich the knowledge of the deep aqueous system. Two typical spectral structures of the hydrograph of the deep aqueous system are obtained by comparing with many water-bearing systems of the Jizhong depression. One is from well Ma-17 and the other is from the well Xinze-5. Finally, the physical models of forming the spectrum of the hydrograph are constructed on the basis of the spectrum research on the deep aqueous system. 相似文献
9.
Abstract The fluctuation of most of the hydrograph in the deep aqueous system records the fluid pulsation in lithosphere and variation of the earth's crust. Many observations have verified that groundwater is an ideal information carrier of the crust. In this paper, the series of input (precipitation, air pressure, Earth tide etc.) and output (water level, artesian flow) of the deep aqueous system are studied by using the spectrum analysis and system theory. The application concepts of transfer function and the spectral structure of the hydrograph enrich the knowledge of the deep aqueous system. Two typical spectral structures of the hydrograph of the deep aqueous system are obtained by comparing with many water—bearing systems of the Jizhong depression. One is from well Ma—17 and the other is from the well Xinze—5. Finally, the physical models of forming the spectrum of the hydrograph are constructed on the basis of the spectrum research on the deep aqueous system. 相似文献
10.
实验矿物物理是高温高压实验地球科学的重要分支学科之一,它主要是通过高温高压实验模拟地球内部的物理化学环境,并原位测定地球深部物质（矿物、岩石和熔/流体等）的相变和状态方程、电导率、热导率等物理参数,探讨地球内部的圈层结构、物质组成、地球动力学过程等地球物理性质相关的一系列重要科学问题. 综述了实验矿物物理的发展历史、近二十年的研究现状与趋势,并展望了该学科未来发展的方向、关键科学问题与面临的主要挑战. 相似文献
11.
Deviation of the major axis of the inertia ellipsoid of the Moon from the direction toward the Earth
B. P. Kondratyev 《Astronomy Reports》2017,61(8):709-714
It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T 3 = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″. 相似文献
12.
基于脉动注浆泵可输出低频周期性脉冲压力的特点,结合可控性黏土固化浆液,提出了一种可用于堤坝防渗加固的新方法。通过进行原型试验验证了该方法的可行性,考虑钻孔扰动和脉动低频重复压力对地层渗透特性的影响,推导了黏土固化浆液脉动扩散方程,运用多场耦合软件COMSOL探讨了脉动压力下黏土固化浆液扩散的机制,最后将研究成果成功应用于南水北调中线鹤壁段引水渠道边坡帷幕注浆工程。研究结果表明：黏土固化浆液脉动控制注浆技术可显著提高地层连续性和整体性,结石体28 d强度大于2 MPa,渗透系数可降至10?5 cm/s左右,浆液在注浆孔附近与土体胶结成块,邻近注浆孔浆脉交错搭接,整体表现为空间立体网状包裹结构的防渗墙体;对数值模拟和现场试验结果进行综合分析,堤坝脉动注浆时间应控制在1 800～2 400 s之间,合理的脉动注浆压力在0.2～2 MPa之间,脉动持续时间宜调至4～8 s,脉动间隔时间宜调至2～6 s,这样有利于保证堤坝脉动注浆工程达到最优的防渗加固效果;工程实践的渠道边坡连续性、整体性得到了改善,注浆止水加固效果显著,检查孔渗透系数降至10?5 cm/s,所取芯样完整,芯样最长可达40 cm。 相似文献
13.
燕山运动为1926年翁文灏所创立,半个多世纪以来,随着地质工作的开展,对中生代地层、岩浆活动和构造形迹特征的深入研究,许多学者曾撰文进行讨论(表1)。燕山运动系指发生于侏罗、白垩纪时期的构造运动。燕山运动形成了华北盖层主要的构造形迹,伴随强烈的岩浆活动,形成丰富的矿产资源,是华北地块显生宙最重要的构造运动。尽管对燕山运动已进行了大量的研究工作,但目前对燕山运动的分期,各期构造活动方式、构造应力场特征,构造演化,构造活动机制等,仍众说纷云,本文将对这些问题进行讨论。 相似文献
14.
15.
Sanjeev Anand Sahu Soniya Chaudhary Pradeep Kumar Saroj Amares Chattopadhyay 《Arabian Journal of Geosciences》2017,10(5):120
The study of surface waves (Rayleigh wave) finds their virtuous applications in a numerous geological and geophysical fields including water, oil, gas, and other subsurface geological probing and exploration. The present paper efforts to investigate the influence of initial stress, Earth magnetism, and gravity on propagation of Rayleigh waves. Considered model is consist of a liquid layer lying over a magnetoelastic orthotropic half-space under self-weight and initial stress. Method of separation of variable is used to solve the equation of motion. Solutions of governing equations are obtained in terms of displacement. Frequency relation for Rayleigh wave has been obtained and matched with classical Rayleigh wave equation. In addition to classical case, some existing results have been deduced as particular case of the present study. Obtained results have been shown through numerical illustrations. It is found that the considered parameters (initial stress, Earth magnetism, and gravity) have prominent effect on phase velocity of Rayleigh wave. Graphical representations have been made to exhibit the velocity profile of Rayleigh waves for different cases with the help of MATHEMATICA. The present study may be useful for seismologists and engineers who are concern with applications of wave propagation in magnetoelastic orthotropic medium. 相似文献
16.
B. P. Kondratyev 《Astronomy Reports》2018,62(10):705-712
It is known that the center of mass (CM) of the Moon does not coincide with its geometrical center of figure (CF), and that the CF–CMline deviates to the Southeast of the direction toward the center of the Earth. An investigation of this phenomenon, which has remained incompletely understood, has been carried out in two stages. One mechanism can explain part of the eastward shift of the lunar CM as being due to tidal evolution of the lunar orbit. A second mechanism is considered here, which relates this shift of the lunar CM with evolution of the shape of the Moon. A differential equation describing the shift of the lunar CMto the East in the course of the physically inevitable rounding of its shape as it moves away from the Earth is derived and solved. This mechanism not only explains the eastward shift of the lunar CM, but also predicts that the oblateness of the Moon could have been appreciable at earlier epochs, reaching values ε ≈ 0.31. The theory of figures of equilibrium in a tidal gravitational field is used to determine how close to the Earth the Moon could have formed. 相似文献
17.
P. I. Dorogokupets 《Geochemistry International》2007,45(6):561-568
A semiempirical equation of state was derived for magnesite under the thermodynamic conditions of the Earth’s mantle. Within experimental uncertainties, it is consistent with thermochemical, ultrasonic, X-ray, and shock-wave data at temperatures from 15 K to the melting point and pressures of up to 100–130 GPa. The following values were recommended for the isothermal bulk modulus and its pressure derivative: K T = 111.71 GPa and K′ = 4.08. Thermodynamic analysis showed that magnesite does not decompose to periclase and CO2 under the thermodynamic conditions of the Earth’s lower mantle and outer core. 相似文献
18.
在时间域航空电磁系统中,采用高频伪随机序列作为激励源是实现浅层高分辨地质探测的有效途径。为了提高大地脉冲响应的辨识精度,在基本相关辨识方法的基础上,本文提出了一种基于时间域循环相关计算的高精度辨识方法,通过消除旁瓣效应影响和在时间域下求解维纳-霍夫方程获取大地脉冲响应。数值模拟仿真结果表明,辨识大地响应相对误差均方根为2.2×10-7,早期大地响应辨识误差小于10-10。该高精度辨识方法具有较好的噪声压制能力,在观测时间较短时,单周期辨识提升的信噪比为8.7 dB,优于同等条件下线性叠加降噪方法提升的信噪比6.1 dB。 相似文献
19.
The process of aeolian flux in wild areas is usually unstable due to turbulent fluctuation of airflow. The physical parameters of wind and aeolian flux have strong pulsation characteristics and are even intermittent. Since the classical aeolian flux equations derived from steady sediment transport processes do not take into account the physical parameters such as soil particle properties and airflow turbulence characteristics, they cannot accurately predict the process of sediment transport driven by turbulent wind. Based on the analysis of the variables contained in the classical aeolian flux equations and their effects on the aeolian flux, the soil particle properties and the airflow turbulent fluctuation which influence unsteady sediment transport process, and the delayed response of the unsteady sediment transport process to airflow turbulent fluctuation, then the steady and unsteady sediment transports were defined. Strictly, there is no steady sediment transport process in nature, but the sediment transport process in a short period of time can be roughly considered to be a steady sediment transport process as the fluctuation of sediment transport is very little. Thus, the unsteady sediment transport process in a long-term series can be regarded as series of steady sediment transport processes on an "appropriate time scale" (Δt). The construction principles, variables in unsteady aeolian flux equation, and establishing unsteady aeolian flux equation of the way which is the method of determining each variable by controlling the conditional experiments were put forward. Finally, the foreseeable key issues in the process of establishing the unsteady aeolian flux equation were discussed. 相似文献
20.
近年来,地球系统科学逐渐成为地球科学的新趋势,但固体地球科学尚难于融入其中。其根本原因在于地球系统科学属于系统科学或复杂科学的组成部分,而固体地球科学其本质上属于理想科学的范畴,以研究线性地球过程为主,或者以理想科学的手法研究非线性地球过程。流体地球科学不仅研究地球的流体系统,也研究流体系统与固体系统的强和弱相互作用,是固体地球科学融入地球系统科学的唯一途径。 相似文献