暗绿色硬质亚粘土层桩基的工程地质条件

本文重点叙述了离地表30米以内暗绿色硬质亚粘土层。此土层在上海地区分布较广,土质坚硬,常作为建(构)筑物的桩基持力层,文章从沉积环境、分布状况、土质特性及桩基承载力四个方面进行了分析探讨,並举实例说明。     

长白山西土顶子3.7级地震前的水氡频谱特征

1986年8月22日长白山火山山深震区西土顶子发生了Ms3.7级浅源有感地震,本文计算了距震中27km的长白山1~#冷泉、2~#温泉及距震中161km的延边地震台山洞冷泉地震前后的水氡富里叶振幅谱。经频谱周期显著性检验后得出,各泉水氡均在震前出现了一定主周期的同步性振幅谱异常。     

从轮藻探讨南海北部大陆架的地层划分对比

根据南海北部大陆架18个钻井561个样品的分析鉴定,说明含有Characeae,Clavatoraceae和营养体三类轮藻。依据化石特征其地层时代为早、晚白垩世,古新世,渐新世和晚第三纪。其中早、晚白垩世和古新世地层的轮藻化石和岩性,可分别与广东陆地上,下白垩统官草湖群,上白垩统大塱山组及古新统(土布)心组和西(土布)组等对比,表明两者在白垩纪—古新世期间连为一体。恩平组沉积后隆升,自渐新世起南海北部大陆架逐渐沉降并形成今日南海。     

综合烃类检测技术及其在早期油藏描述中的应用

烃类检测是早期油藏描述的重要任务之一,根据对我国东部几个含油气构造实际资料研究,提出了如下三种方法:1.应用亮点原理确定烃类的地震模式及其在纵向上的分布特征;2.应用AVO技术,进一步确定地震储层和垂向分布特征以及划分油气边界;3.在以上研究基础上,我们提出了一种利用多种地震参数进行烃类综合检测的方法及实现过程。文中给出了一些实例来说明方法的使用效果。在不断的完善和充实之后,这些方法会在油气勘探过程中得到广泛的应用。     

地电阻率的相干加强分析

本文介绍了相干加强的原理及其在地电阻率分析预报地震中的应用研究，计算了大柏舍台和宝坻台ρ＿ｓ连续几年的资料，结果发现地震前ρ＿ｓ有较为突出的短临异常．     

南水北调中线工程对汉江中下游的影响分析

本文分别计算了丹江口水库１９６９－１９９０年实际下泄流量过程和大坝加高向黄淮海地区调水１５×１０９ｍ３后下泄过程在２０２０水平年下汉江中下游各点的水位流量过程，比较了两者的水位流量差①，分析了丹江口水库调水对汉江中下游各点水位和流量的影响以及引起的灌溉用水和航运的变化。结果表明，丹江口水库调水后，丹江口水库下游各点的多年平均水位、流量将下降，流量过程趋于缓和，洪水流量减少，枯水流量增加；灌溉取水量减少，破坏状况加重，枯水期航运流量增加，但中水期航运时段减少。最后，作者对汉江中下游补偿工程提出了建议。     

钻探工艺,取土方法与取土器结构对勘探质量和不扰动土样取土质量的影响

本文通过对比试验和生产实践的总结,分析了钻探工艺、取土方法和取土器结构对勘探质量和不扰动土样取土质量的影响,并提出了保证勘探、原状取土、标准贯入试验质量的一些具体设想和方法。     

Semi-Analytical Solution for Stresses and Displacements in a Tunnel Excavated in Transversely Isotropic Formation with Non-Linear Behavior

A semi-analytical solution based on the transfer matrix technique is proposed to analyze the stresses and displacements in a two-dimensional circular opening excavated in transversely isotropic formation with non-linear behavior. A non-isotropic far field can be accounted for and the process of excavation is simulated by progressive reduction of the internal radial stress. A hyperbolic stress–strain law is proposed to take into account the non-linear behavior of the rock. The model contains seven independent parameters corresponding to the five elastic constants of an elastic material with transverse isotropy and to the friction coefficient and cohesion along the parallel joints (weakness planes). This approach is based on the discretization of the space into concentric rings. It requires the establishment of elementary solutions corresponding to the stress and displacement fields inside each ring for given conditions at its boundaries. These solutions, based on complex variable theory, are obtained in the form of infinite series. The appropriate number of terms to be kept for acceptable approximation is discussed. This non-linear model is applied to back analyze the convergence measurements of Saint-Martin-la-Porte access gallery. Short-term and long-term ground parameters are evaluated.     

Hard x-ray and Metric/Decimetric Radio Observations of the 20 February 2002 Solar Flare

The GOES C7.5 flare on 20 February 2002 at 11:07 UT is one of the first solar flares observed by RHESSI at X-ray wavelengths. It was simultaneously observed at metric/decimetric wavelengths by the Nançay radioheliograph (NRH) which provided images of the flare between 450 and 150 MHz. We present a first comparison of the hard X-ray images observed with RHESSI and of the radio emission sites observed by the NRH. This first analysis shows that: (1) there is a close occurrence between the production of the HXR-radiating most energetic electrons and the injection of radio-emitting non-thermal electrons at all heights in the corona, (2) modifications with time in the pattern of the HXR sources above 25 keV and of the decimetric radio sources at 410 MHz are observed occurring on similar time periods, (3) in the late phase of the most energetic HXR peak, a weak radio source is observed at high frequencies, overlying the EUV magnetic loops seen in the vicinity of the X-ray flaring sites above 12 keV. These preliminary results illustrate the potential of combining RHESSI and NRH images for the study of electron acceleration and transport in flares.