瞬变电磁法中两种关断电流对响应函数的影响及其应对策略

关断时间是影响瞬变电磁资料处理和解释质量的一个重要因素 ,也是衡量TEM仪器性能的一个关键参数。提出了一种直接数值校正方案 ,并通过对线性和指数关断电流的校正描述了该方案的实施过程。根据文中提出的方案 ,只要仪器记录了一次场的衰减曲线 ,就可以进行较为精确的校正 ,并不必要假设线性衰减或指数衰减 ,这一结论无论是对TEM的仪器设计还是数据处理都具有重要意义     

结构隔震的研究与应用综述

结构基底隔震是房屋免震的新方法，在国外，这种方法已应用于土建工程。本文介绍基底隔震研究的进展和应用情况。     

微重力方法在考古工程中的应用：——明茂陵地下陵殿探查

根据微重力和重力垂直梯度方法对已知地下物质体（定陵地下宫殿）的验测所取得的信息与经验，对于地下未知物质体（茂陵的地下建筑物）进行了探测。在微重力探查的基础上，预测了茂陵地下陵殿的分布形态，所在位置等。此结果可供有关考古部门参考使用，同时也表明微重力方法在考古工程方面具有很广的应用前景和实用价值。     

利用地方震出格记录尾波测定宁夏北部及邻区Q值

基于安艺的尾波理论,本文提出了一种使用单台记录的出格地震图尾波资料测定地壳上层介质Q值的新方法。利用该方法,对宁夏北部地区(38°—41.5°,104°—107°)测定了其Q值的分布。结果指出,宁夏吴忠到石咀山之间的银川地堑的Q值(100—200)明显偏低于与其接邻的内蒙阿拉善左旗和磴口一带的Q值(200—300),在个别局部区城存在Q值异常区。最后简要讨论了所得结果。     

DETERMINATION OF LATERAL INHOMOGENEITIES IN REFLECTION SEISMICS BY INVERSION OF TRAVELTIME RESIDUALS*

Lateral inhomogeneities generate fluctuations in the traveltime of seismic waves. By evaluation of these traveltime fluctuations from different source and receiver positions, lateral inhomogeneities can be located using a pseudo inverse matrix method (Aki, Christoffersson and Husebye 1977). The formulation of the problem is possible for transmitted waves as well as for reflected and refracted waves. In reflection seismics this method is of importance, if no reflections from the inhomogeneities themselves, but only reflections from lower boundaries can be observed. The basic assumptions for the mathematical formulation are (1) the average velocities and depths of the reflecting horizons are known already from standard processing methods, and (2) the traveltime residuals are due to lateral velocity changes between different reflectors or between reflectors and the surface. The area of the earth to be considered is divided into layers and the layers into rectangular blocks. The parallel displacement of a ray after passing a disturbed block is neglected, only the traveltime residual is taken into account. In this paper the method and its application to data obtained with two-dimensional models are described.     

固体潮磁带记录的重取样及强地震干扰的消除

本文讨论取样间距为5s的固体潮磁带数据的重取样及消除强地震干扰的方法.所提出的多项式拟合平滑取样方法(PFSS)使读带、平滑、取样同步进行.读带一结束,计算机内存就有了按给定间距的取样结果.由于只对有关点作格式变换和预处理,故可以节省计算时间;由于只存取样结果,故可以节省计算机空间.因此,这种方法适用于小间距而延续时间长的固体潮磁带数据.采用功率谱分析,并对PFSS方法的结果作了检验,证明这种方法具有良好的滤波功能.为了消除强地震干扰所引起的畸变,采用Nakai方法并给出迭代程序,也用谱分析作了检验.校正后的观测数据,其谱分析结果与理论潮结果相似.      

测定浅震震源参数的宏观方法

本文提出了利用等震线测定地震断层面的走向、倾向、倾角和破裂长度等震源参数的宏观方法。用这种方法测定了35个地震（1830年-1973年）的参数,其结果与用微观方法得到的结果进行了比较,二者基本一致。 关于破裂方式对等震线的影响问题,本文也进行了初步的讨论。     

降雨对地电阻率干扰的分析

在一些地电阻率观测台站受本身台址条件的限制，观测深度较浅，因此，观测值受到降雨等气象因素的影响。本文选取昌黎台ＥＷ向１９８３－１９９４年观测资料月均值，用褶积滤波和多元回归方法对ρｓ进行了降雨校正，将将之作为一个灰箱系统，将资料外推至１９９５４上，然后与原始观测值作残差分析，取得了一定效果。     

基于自平衡力的弹塑性动力反应分析方法

本文给出了一个基于自平衡力的弹塑性结构动力反应分析的新方法，详细叙述了方法的原理和过程，并对用改进的Ｔａｋｅｄａ滞变模型描述的梁单元框架结构给出了具体的分析方法。这个方法与传统的方法不同，在分析中不必修正结构的刚度矩阵，而代之以计算代表塑性铰变形引起的应力重分布的动力自平衡力，因而大大地节省了计算机时，最后通过算例对本文方法进行了验证。     

地壳块体脉冲响应的时间反转效应研究

运用动态有限元方法，对地壳块体脉冲响应的时间反转过程进行了仿真研究．结果表明，分布在较长时段上的量值较小的变化载荷，在一定的构造条件或边界条件下有可能累积成一个时间短、量值高的脉冲．这一过程在物理上表现为先头发出的波与后继发出的波发生了多次叠加或干涉．在这个认识基础上，对孕震以及发震的机理提出了新的看法，并就华北块体对渤海、黄海潮汐动态响应的仿真结果，进一步作出理论上的解释．      

烈度分布的几何特征和震源参数的估计

本文在考虑环境刚度效应和非匀阻效应的情况下,采用椭圆形震源简化模型,研究了走滑断层的地震烈度几何要素与震源参数之间的关系,初步建立了估计断层有效发震段长度、错动角、应力降和错动距离等参数的等震线法,并结合唐山、通海、炉霍和永善等震例进行了试算     

AUTOMATED ANALYSIS OF PUMPING TESTS IN UNCONFINED AQUIFERS OF SEMI-INFINITE THICKNESS

Abstract A procedure is described for automated fitting of test data for pumping from an unconfined aquifer of semi-infinite thickness. The fitting is achieved by sensitivity analysis and the least-squares method. The early time data are fitted to the Streltsova (1974) model and the late time data are matched to the Dagan (1967) model. These solutions are useful where the aquifer thickness is extensive and unknown. Data from a test in the Indus Basin, Pakistan, was analyzed to test this procedure.     

一种修定震源参数的方法

本文描述了空间域中的一种定位方法。此方法的主要特点是:1.震中位置与震源深度、发震时刻分离求解;2.震中位置的确定是采用Romney提出的曾融生改进的台偶到时差来建立最小平方条件方程,几乎不受结构的影响;3.震源深度和发震时刻的确定是采用慢度定深度、到时曲线时间截距定发震时刻的方法来实现的。本文用四川境内的5个工业爆破资料,作了方法试验并修定了近年发生的50个天然地震。修定后的震中位置更加靠近断裂带,走时残差减小了,震源深度呈现出沿龙门山断裂由北东向南西逐渐加深的规律性。     

地震空区的定量判据

在中国，孕震空间已经比较广泛地应用于地震预报的实践，并多次取得实际预测强震的效果。但经过系统震例研究发现，利用孕震空间预报地震的虚报漏报率比较高。本文运用解决临界相变问题的重正化群方法所求出的孕震空间区可能发生失稳破裂，导致强震发生的判据对孕震空间的危险性作出进一步鉴别，并用突变论方法求解尖拐空变方程，预测孕震空区未来发生强震的时间和震级，并进一步确定孕震空区的危险性。对２６个中国大陆强有的孕震空     

THE MAXIMUM LIKELIHOOD ESTIMATION OF b-VALUE IN MAGNITUDE-FREQUENCY RELATION AND ANALYSIS OF ITS INFLUENCING FACTORS

b-value in the magnitude-frequency(G-R)relationship plays a vital role in seismicity research and seismic hazard analysis, and the most commonly used techniques to simulate it are least square approach and maximum likelihood method. Least square method is simple and easy to apply, therefore widely used in China. However, many researches show that there exist some limits in least square estimation of b-value. Earthquakes with different magnitudes are not equally weighted in this method, and larger events have higher weights, so b-value is vulnerable to the fluctuation of several big earthquakes; meanwhile, least square method needs to divide magnitude intervals artificially. With a small sample size, data points could be not enough if the magnitude interval is too wide, and events in a magnitude interval may be lacking if it is divided to be too narrow. Especially for incremental G-R relationship, it is possible that N(M_i)equals 0 in an interval with large magnitude, so log(N(M_i))loses meaning and has to be ignored, resulting in a low b-value. Therefore, under certain conditions, maximum likelihood method is recommended as an effective substitution or supplementary for least square estimation of b-value. Among numerous previous researches on maximum likelihood estimation of b-value, lots of equations have been provided, based on varied implicit assumptions and different ways of solution. A brief overview is first presented for these equations, and classification and summary are provided based on whether taking account of the effect of binned magnitude, with finite maximum magnitude, using unequal observation periods for different magnitude intervals, and with analytic solution or not. Following this, a total of 6 influential factors are analyzed, such as binning magnitude, measurement errors of magnitude, sample size, magnitude span, minimum completeness magnitude and fore- and aftershocks. At last, reasonable suggestions are provided for using those equations properly. The equations of Aki(1965), Utsu(1965), Page(1968)and Kijko and Smit(2012)are based on assumption that magnitudes are continuous random variables, and have no corrections for this, so these equations are not recommended here. For simplicity, the equations of Utsu(1966)or Tinti and Mulargia(1987)can be used, but magnitude span should be greater than 2.5 due to without finite maximum magnitude in the formulas. For researchers having capability to write code and calculate numerically, Weichert(1980)or Bender(1983)'s algorithm could be utilized. Especially when it is required to apply data with different observation periods for varied magnitudes, the formula of Weichert(1980)is recommended. This study contributes to more accurately understand and use different formulas of estimating b-value by maximum likelihood technique, which can be used as reference for peers.     

地震波走时和射线的有限差分计算

以往都是采用射线追踪的方法计算地震波的走时和射线，但是当速度模型复杂时这种方法存在一些问题。本文提出另一种计算地震波走时和射线的方法。该方法从程函方程出发，利用互换原理和Ｆｅｒｍａｔ原理计算出各种波的到时和射线。解决了射线追踪方法存在的问题。为地震波走时和射线的计算以及地震波走时反演开辟了一条新途径。     

原地宇宙成因核素测年中石英样品分离提纯的几组实验对比

原地宇宙成因核素测年方法在地质及地理研究领域应用广泛,测年对象众多。石英因其致密的晶体结构不易被大气成因10Be污染,以及较低的27Al含量的特点而成为宇宙成因核素测年方法中一种理想的测年物质。在分离石英样品10Be和26Al的实验流程中,石英的提纯是其中的一个关键环节。原始的HCl/H2O2和HF/HNO3蚀刻分离提纯石英方法应用广泛、安全可靠,但处理样品周期长、效率较低。因此,在原始流程的基础上,设计了3组实验流程与原始流程进行对比。结果显示,在样品石英纯度较高的基础上,可以通过减少超声波使用时间、增加蚀刻溶液浓度及每步样品处理量的方法,提高样品的处理效率,同时可以用加热磁力搅拌器替代超声波清洗器进行石英样品的HF/HNO3蚀刻提纯     

晋中南地区地壳结构的初步研究

本文是对陕西长安、山西代县和太谷等地工业爆破的资料采用时间项法研究晋中南地壳结构的初步成果。文中首先结合长安爆破观测资料的总结,对时间项方法作一介绍。为使用太谷等缺乏起爆时刻的爆破资料,对时间项方法作了一些改进,使对于那些未有起爆时刻的爆破资料亦能用于确定时间项。使用上述爆破和各台记录的初动到时获得了晋中南地区的界面速度为7.95±0.04公里/秒,求得了41个点的时间项,取莫霍面以上介质的平均速度v₀=6.4公里/秒反演求得了各点的莫霍界面深度,并对所得的结果结合晋中南地区的地震活动性及部分地震震源机制结果进行了初步的分析和讨论。     

弹性地球负荷潮汐应变的理论及计算

本文概述了弹性地球负荷潮汐应变的理论,研究了计算负荷勒甫数的递推算法,并对处理褶积积分的基本方法及过程作了讨论,给出了有关的工作公式。     

FRACTIONAL TRANSPORT OF SEDIMENT MIXTURES

A new method based on the Transport Capacity Fraction (TCF) concept is proposed to compute the fractional transport rates for nonuniform sediment mixtures in sand-bed channels. The TCF concept is derived from the understanding that the measurements and predictions of bed-material load are more accurate and reliable than the measurements and predictions of fractional loads. First the bed-material load is computed using an appropriate equation, then the fractional transport rates are determined by distributing the bed-material load into size groups through a transport capacity distribution function. For the computation of bed-material loads, the Ackers and White, Engelund and Hansen, and Yang equations are used in this study. Two new transport capacity distribution functions are developed for flows in sand-bed channels. The new expressions presented in this paper account for the sheltering and exposure effects that exist in mixtures. Comparisons with measured data show that the proposed method can signifi