The System Analysis and Reliability Evaluation of Rock Slopes   总被引：1，自引：0，他引：1  

Luo Guoyu  Yan ChanghongDepartment of Earth Sciences  Nanjing University  Nanjing  Jiangsu Fei Zhenbi 《《地质学报》英文版》1994,68(4)

The principal of preferred plane analysis is a new research view and model of rock slope engineering geology. It advocates that the rock slope stability, boundary conditions and failure model are controlled by preferred planes. Therefore, the problem of slope stability evaluation can be converted into the search for preferred planes and determination of preferred separating bodies. The organic combination of the deterministic model and the indeterministic model can be realized by applying the systems engineering principle and the research model and method of reliability analysis in the quantitative evaluation and prediction of rock slope stability. Finally, the paper presents the case studies of slopes of the Yangtze Gorge Project and the Ma'anshan openpit mine.  相似文献   

铁路工程地质选线咨询系统   总被引：3，自引：0，他引：3  

乔平  王云鹏 《工程地质学报》1994,2(4):77-83

本文考虑了铁路线位选择的特点，从地质的角度出发，将铁路地质选线中涉及的主要问题（滑坡、泥石流、风沙、岩溶）归纳、总结建立知识库，通过推理为铁路总体选线提供地质依据，以减少工程失误，节约工程造价，保证工期。本文重点介绍该系统的组成部分及各个部分的具本设计思想和设计技巧。  相似文献   

宁夏石炭纪、早二叠世孢子带和石炭─二叠系界线     

高联达 《甘肃地质》1994,(1):11-26,101,104

宁夏中宁、中卫地区石炭系和二叠系地层发育，化石丰富，是我国石炭—二叠系地层重要研究地区。首次系统的孢粉地层学研究，共发现６０余属、１８Ｏ余种孢子和花粉。根据孢子花粉在地层中演化规律，可划分出１０个孢粉组合带，其中石炭系８个带，下二叠统２个带。中宁、中卫地区石炭系和下二叠统孢粉组合带可与甘肃靖远和华北地区同时代孢子带比较，亦可与西欧，北美和前苏联有关孢子带对比。中宁、中卫地区石炭系和下二叠统孢粉带的研究不仅有重要地层学和古生物学意义，而且对该地区石炭系和石炭—二叠系界线划分与对比有重要意义，对研究华北地台和祁连褶皱带之间关系以及沉积环境和古地理的研究也十分重要。  相似文献   

甘肃的寒武系   总被引：1，自引：0，他引：1  

俞伯达 《甘肃地质》1994,(Z1):1-53

寒武系主要分布于北山、祁连山、河西走廊及陕甘宁盆地。根据沉积岩相及动物地理区系分为三大沉积区和７个沉积分区：北山沉积区分为下统双鹰山组、中统大豁落井组、上统西双鹰山组；祁连山沉积区未见下统，中统月牙山群、黑茨沟群和格尔莫沟群，上统香毛山群；华北沉积区下统未分，中统毛庄组、徐庄组和张夏组，上统仅见崮山组。三大沉积区的动物群分别为东南型（除早寒武世外）、过渡型和华北型。寒武系下界相当于滇东的沧浪铺阶之底界，并与震旦系冰碛层呈平行不整合接触。寒武纪岩相古地理轮廓受当时的地壳变动和气候条件所控制。早寒武世中晚期开始海侵，在北山沉积区之西部呈海湾，在陕甘宁盆地西缘呈浅海陆棚，省内其余地区（除西秦岭外）呈古陆状态。中寒武世广泛海侵，在祁连山形成海槽，且地壳运动加剧，火山喷发活动频繁。晚寒武世大规模海退，仅在北山局部地区、祁连山西段和陕甘宁盆地有沉积，其余均为古陆状态。  相似文献   

Simulation of flow over pool-riffle topography: A consideration of the velocity reversal hypothesis     

P. A. Carling  N. Wood 《地球表面变化过程与地形》1994,19(4):319-332

Computer flow simulations using the HEC-2 step-backwater routine are used to demonstrate the effect of systematically varying river channel width, riffle spacing and channel roughness on the shear velocity, section-mean velocity and energy slope in fixed-bed pool-riffle sequences. Initial scaling is obtained by utilizing published information on hydraulic parameters within reaches of the River Severn. Subsequently this restriction is relaxed and the effect of varying parameter combinations within realistic limits is explored. The purpose of this exercise is to isolate those scenarios which may preclude or promote the occurrence of a competence ‘reversal’, such that pools scour at high flow whilst deposition occurs on riffles. It is concluded that rivers in which pools are hydraulically rougher than riffles are likely to demonstrate a competence reversal. For prescribed conditions, the critical discharge at which a reversal occurs is a negative function of riffle spacing and riffle width relative to pool width. Downstream variation in hydraulic roughness also has implications for the phase relationship of shear velocity maxima and minima in relation to the extremes in pool-riffle topography.  相似文献   

An object-oriented knowledge representation structure for exploration data integration     

P. An  W. M. Moon  G. F. Bonham-Carter 《Natural Resources Research》1994,3(2):132-145

Knowledge representation structure and reasoning processes are very important issues in the knowledge-based approach of integrating multiple spatial data sets for resource exploration. An object-oriented knowledge representation structure and corresponding reasoning processes are formulated and tested in this research on the knowledge-based approach of integrating spatial exploration data. The map-based prototype expert system developed in this study has self-contained knowledge representation structure and inference mechanisms. It is important to distinguish between lack of information and information providing negative evidence for a map-based system because the spatial distribution of data sets are uneven in most cases. Error and uncertainty estimation is also an important component of any production expert system. The uncertainty propagation mechanisms developed here work well for this type of integrated exploration problem. Evidential bellef function theory provides a natural theoretical basis for representing and integrating spatially uneven geophysical and geological information. The prototype system is tested using real mineral exploration data sets from the Snow Lake area, northern Manitoba, Canada. The test results outline the favorable exploration areas successfully and show the effectiveness of the knowledge representation structure and inference mechanisms for the knowledge-based approach.  相似文献   

大庆-哈尔滨地段地热资源研究   总被引：1，自引：0，他引：1  

赵继昌  宋鹤彬  高鹏飞 《地球学报》1994,15(Z1):168-176

作者应用地下水系统理论,从古水文地质条件及现代地下水动力场特征入手,通过水文地球化学和环境同位素地球化学研究,探讨了松辽盆地中段的地热及其赋存特征,认为盆地的大部分地区温梯度都较高,具有形成深部地热的条件,但只在上部具有较厚的含水层及断裂发育凹陷带中的局部地区,才能赋存可开采的地下热水资源。  相似文献   

电气石和水之间的氢同位素分馏   总被引：1，自引：0，他引：1  

钱雅倩  郭吉保 《地球学报》1994,15(Z1):189-196

作者对电气-水体系氢同位素平衡分馏和动力学分馏和动力学分馏开展了实验研究，丰富了羟基矿物氢同位素分馏资料。本文对该研究的实验技术、分析方法作了介绍，并对实验结果进行讨论与国外已有的该方面的资料作了对比。在800-650℃时电气石和水之间氢同位素平衡分馏系数与温度间线性关系为103lna电气石-水=-28.24（106/T2）+2.60；交换速率常数与温度间关系为lnk2=-0.19-6.70（103/T）  相似文献   

广西灌阳地区碳酸盐岩层滑断裂构造地球化学系统   总被引：10，自引：1，他引：10  

钱建平 《矿物学报》1994,14(4):348-356

灌阳地区碳酸盐岩中的层滑断裂构造地球化学系统具有典型的结构分带性、变形二重性和成分互补性。在这个系统中存在着Cu→Fe3 →V→Si→Al→Mn→Ba→Ni→Sr→Ag→Bi→Ga→In→Pb→Fe2 →Cr→Co→Zn→Mg→Ca→CO2的稳定性递减序列。影响构造地球化学分异的因素是原岩的性质、应力、温度和流体。构造地球化学作用的基本类型有：动力分异作用、压溶作用和氧化还原作用。层滑断裂带并非还原环境，碳质富集源自有机碳的氧化。Sr是高应力环境同构造重结晶方解石带的特征元素，Zn是低应力环境裂隙充填型方解石脉的特征元素。  相似文献   

中国南方下寒武统石煤的特征,沉积,环境和成因   总被引：4，自引：0，他引：4  

姜月华  岳文浙 《中国煤田地质》1994,6(4):26-31

在早寒武世，中国南方存在着四种类型的含石煤地层一南岭型、扬子型、江南型和华南型，其中的石煤在量和质的方面均各不用问，据研究，这主要与当时的沉积背景（一个浅水台地、一个深水盆地和三个深水大陆斜坡）差异有关。作者通过对石煤的分布、厚度、物质组分、岩石类型、物理化学性质和伴生元素的讨论，认为其形成机理为：海平面上升，由上升洋流携带富养海水在沉积速率缓慢和少泥的条件下，促使菌藻类大量发育，并由此引起海底缺氧环境；菌藻类死亡后沉积在海底，经过复杂的成岩变质作用就形成了石煤。  相似文献