瞬变电磁场的奇点展开法

在分析电磁系统自然谐振现象的基础上,简述了瞬变电磁场奇点展开法的物理基础、基本理论、极点提取方法,并考查了奇点展开法在地球物理中的应用可能性。     

双频梯度测量探查井巷漏水水力联系

介绍一种利用双频仪解决矿区井巷巷道中漏水水力联系的原理和方法。双频梯度测量法有抗干扰能力强、分辨率高、仪器轻便等特点,实践证明应用效果很好。     

试论HACSAMT法

HACSAMT法在不增加任何设备、工作人员、工作时间的前提下,观测基波信号的同时,采集其高次谐波的振幅和相位的数据,大大地提高了劳动效率,而且,由于运用了谐波的有用信号,加密了CSAMT法勘探的频率,从而,提高了CSANT法的纵向勘探分辨率     

深层搅拌桩复合地基的有限元分析

介绍了用自行编制的适用于群桩地基基础应力、变形分析的三维非线性程序对一种有代表性的群桩进行分析的情况。讨论了深层搅拌桩复合地基的工作机制和应力、变形分布特点，并通过多种方案的比较就不同的荷载水平、桩长、桩上置换率、土层分布、桩身变形模量等诸因素对地基沉降、桩端应力、桩的承载率的影响和规律进行了研究。     

深基坑排桩—圈梁支护结构协同作用研究

排桩－圈梁的协同作用对深基坑支护结构的变形和内力有着重要的影响，为此对深基坑排极支护结构进行了弹性地基梁有限元分析，得出一些有意义的结论。     

江西广丰地区中奥陶统层序地层分析

本文通过对广丰县周家坞中奥陶统露头剖面层序、体系域、副层序的研究，识别出了三个不同性质的Ⅱ型层序界面和二个三级层序，确认这三个层序界面为符合实际又易于野外识别的自然界面，并对ＳＱ２中反映最大海泛期的高分辨异旋回驱动机制事件，提出可能受米兰柯维奇频率的春分点和秋分点间约２万年间隔的控制。     

口泉沟南水源地环境同位素研究和水资源评价

分析了大同矿区口泉沟南区的水文地质条件，利用氢，氧，铀，硫，碳等环境同位素研究了口泉南与相邻的泉域和三层洞泉域的关系及地下水的补给来源；用有限元法进行了地下水资源评价和水位预报，证明在该区建立供水１０＾４ｍ＾３的水源地是可能的。     

Seismic Ground Motion Expected for the Eastern District of Naples

The seismic ground motion of a test area in the eastern district of Naples is computed with a hybrid technique based on the mode summation and the finite difference methods. This technique allows us the realistic modelling of source and propagation effects, including local soil conditions. In the modelling, we consider the 1980 Irpinia earthquake, a good example of strong shaking for the area of Naples, which is located about 90 km from the epicenter.The detailed geological setting is reconstructed from a large number of drillings. The sub-soil is mainly formed by alluvial (ash, stratified sand and peat) and pyroclastic materials overlying a pyroclastic rock (yellow neapolitan tuff), representing the neapolitan bedrock. The detailed information available on mechanical properties of the sub-soil and its geometry warrants the application of the sophisticated hybrid technique.As expected, the sedimentary cover causes an increase of the signal's amplitudes and duration. If thin peat layers are present, the amplification effects are reduced, and the peak ground accelerations are similar to those observed for the bedrock model. This can be explained by the backscattering of wave energy at such layers, that tend to seismically decouple the upper from the lower part of the structure.For SH-waves, the influence of the variations of the S-wave velocities on the spectral amplification is studied, by considering locally measured velocities and values determined from near-by down-hole measurements. The comparison between the computed spectral amplifications confirms the key role of an accurate determination of the seismic velocities of the different layers.The comparison performed between a realistic 2-D seismic response and a standard 1-D response, based on the vertical propagation of waves in a plane layered structure, shows considerable difference, from which it is evident that serious caution must be taken in the modelling of expected ground motion at a specific site.     

Soil-structure interaction analysis of the Hualien containment model

This paper presents results from forced vibration tests, microtremor observations and earthquake response analysis of a nuclear reactor containment model constructed on stiff soil in Hualien, Taiwan. The dynamic behavior of the soil-structure system is simulated successfully with two numerical models: a sway-rocking model, whose soil parameters are evaluated on the basis of the continuum formulation method, and a finite element model, using the program SASSI with the flexible volume substructuring approach. The dependences of the soil parameters of both models on the amplitudes of the different dynamic excitations are investigated in detail. An original numerical simulation of microtremor is performed. Comparison with results of a previous study involving a rigid tower on a soft soil site in Chiba, Japan is offered.     

Attenuation of coda waves and Q c value beneath the Chengdu telemetered seismic network

Based on the single scattering model of coda power spectrum analysis, digital waveform data of 50 events recorded by the real-time processing system of the Chengdu telemetry network are analyzed to estimate the Q _c values of earth medium beneath the Chengdu telemetry network for several specified frequencies. It is found that the Q _c shows the frequency dependency in the form of Q _c = Q ₀ f ⁿ in the range of 1.0 to 20.0Hz. Estimated Q ₀ ranges from 60.83 to 178.05, and n is found to be 0.713 to 1.159. The average value of Q ₀ and n are 117 and 0.978 respectively. This result indicates the strong frequency dependency of the attenuation of coda waves beneath the Chengdu telemetry network. Comparing with the results obtained in other regions of the world, it is found that Q ₀ ⁻¹ value and its change with frequency are similar to those in regions with strong tectonic activity. This subject is supported by the Ministry of Personnel, China for partly sponsoring.