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1.
以29口钻孔的重矿物百分含量数据来分析样本,通过Q型聚类分析、因子分析方法恢复不同物源体系的发育范围及其母岩类型,并以不同物源体系的边界范围为限定条件,结合ZTR指数及其等值线图,对珠江口盆地惠州凹陷M层物源特征进行了系统的研究。研究结果表明:研究区发育3大物源沉积区,分别为东北-北部物源沉积区、西北物源沉积区和东南物源沉积区,且各区重矿物组合特征明显,主次物源分明,整体表现为母岩类型复杂的特征。东北-北部沉积物主要母岩为酸性岩浆岩,次要母岩为变质岩和沉积岩,西北沉积物主要母岩为中性及基性岩浆岩,次要母岩为酸性岩浆岩和变质岩,东南沉积物主要母岩为中性及基性岩浆岩,次要母岩为变质岩。东北-北部物源区和西北物源区为远源沉积的产物,而东南物源区为近源沉积的产物。东北-北部物源区沉积物来自北方和东北方向,而西北物源区和东南物源区沉积物分别来自西北方向和东南方向。  相似文献   

2.
两种煤质分析指标的关联方程组研究   总被引:5,自引:0,他引:5  
在综合分析大量文献资料的基础上,采用多元线性回归方法,利用MATLAB对大量煤质分析结果进行了回归分析,推导出了煤质元素分析与工业分析的关联方程组。新方法实现了由工业分析结果求元素分析成分的目的,具有重大的实用意义。  相似文献   

3.
An algorithm andFortran-iv computer program,cabfac, forQ-mode factor analysis is described. The program will accept up to 1500 items and 50 variables on a moderate-size computer.  相似文献   

4.
In this paper, we report on the use of Bayesian networks, BNs, learnt from data generated by physical and numerical models, to overcome to a certain degree a number of complications in traditional slope stability analyses that jointly consider the mechanical and hydraulic properties of soils. Discrete Bayesian networks resulted to be useful and efficient to acquire knowledge from simulated data and to identify significant factors by the combined use of backward inference and global sensitivity analysis. Further, BNs enable decision thresholds to be estimated quickly. Along with this, backward inference and global sensitivity analysis are performed in BNs at low computation costs. Moreover, under conditions in which knowledge is scarce, we show how a practitioner can be better informed using the proposed approach. All these previously under-reported modelling features in the specialised literature encourage the further application of the proposed approach to enhance slope stability analysis.  相似文献   

5.
A piston core from the southern Blake Basin penetrated nine distinct bioclastic carbonate turbidites separated by pelagic terrigenous clay units. X-ray diffraction analysis of the carbonate mineralogy of the graded, laminated, and homogenous units of the individual turbidite units indicated a general loss of unstable carbonates in the homogenous unit beyond that contained in the lower two units. Univariate and multivariate statistical tests were employed to determine the significance of the changes and to determine if different units of a turbidite sequence could be consistently grouped by statistical methods. Principal components, discriminant function, and cluster analysis were used in the multivariate tests. The graded and laminated units were closely related in mineralogy with little significant differences. The mineralogy of the homogenous units was significantly different than that of the other two units except in one example. Cluster analysis generated five groupings of the samples with the end members consisting of graded and laminated units at one end and homogenous units at the other.  相似文献   

6.
以有限元结构矩阵分析为理论基础,结合应力应变测试和现场实际使用情况,利用计算机结构分析程序,对ZT-A系列三个不同高度钻塔的天梁、塔腿和绷绳做了结构应力分析,弄清了A形塔在承受垂直荷载、水平荷载以及偏载条件下,组成钻塔的各构件的荷载及应力分布;对钻塔设计提出了改进意见;并从整体角度分析了绷绳的作用;对在不同荷载条件下有无绷绳时钻塔的结构应力从量上做了对比;最后提出了应当如何布置提升系统才会使钻塔处  相似文献   

7.
Finite element limit analysis with plane strain condition is employed to determine the upper and lower bound solutions of the undrained limiting pressure behind soil gaps and the lateral force acting on a pile per unit length in a contiguous pile wall. Computed bound solutions confirm serious limitations of existing studies in predicting these two solutions. Predicted failure mechanisms and the arching effect behind soil gaps are discussed. A closed-form equation of the limiting pressure factor is proposed for a convenient and accurate prediction of the lateral force acting on a pile in contiguous pile walls in practice.  相似文献   

8.
On the basis of samples taken from a known topographic surface, the parameters of two types of linear models are estimated. The first category is defined by polynomials or trigonometric functions, whose parameters are simultaneously computed from available data. In the second category a set of local centers is defined, and in the neighborhood of each center a fixed-degree polynomial is developed. An approximative resemblance index is calculated, and contour maps corresponding to various models are compared with the topographic map. It is found that with an increasing number of grid points, maps of local polynomials are converging both in continuity and in resemblance. For a sufficient number of grid points, this resemblance is always higher than those produced by models of the first category.  相似文献   

9.
正Shrimps of genus Artemia are the inhabitants of continental and marine waters with salinity of 70 to 350 g/l and above.Artemia is able to survive in the conditions in which other animals cannot exist.This is due to adaptations:effective osmoregulation system,the ability to synthesize of respiratory pigment(hemoglobin)and diapauses cysts(Litvinenko at.al.,2009).Cysts of this  相似文献   

10.
A deformation mechanism is described and analyzed. It is intended for height patterns exposed to erosion and tectonic activity. A simulation experiment is carried out for this model. Closedform expressions are derived for the covariance field, the properties of spectral estimates, and for the optimal retrospective reconstruction of earlier, unknown height patterns. For obvious reasons the author is in no position to make claims about the verisimilitude of the model. It is offered as an example of a potential application to geology of the theory of patterns developed by the author and his coworkers in recent years. It is hoped that those more qualified than the author in the subject matter area can extend and modify the analysis to make it closer to geological reality. supported by NSF grant GJ-3100X.  相似文献   

11.
近年来随着石油勘探与开发,越来越多的人认识到天文地层学研究在油田生储盖地质年龄和剥蚀量的计算中是对油气资源评价的一个不可缺少的工作环节。中石化胜利油田地质科学研究院在三年的研究基础上借助于Matlab平台,开发出了“旋回地层学研究系统”(Version1.0),该系统在中石化  相似文献   

12.
    
Recent advances in image analysis techniques have allowed rapid generation of peripheral points of two-dimensional objects. Such points, defining overall shape of an object, have been analyzed using several techniques including geometric shape analysis, Fourier analysis, and, more recently, by eigenshape analysis. The latter technique purports to represent a general, optimal, and universally best technique to analyze shapes of fossils. Such a technique was devised allegedly due to failure of exisiting techniques. We seriously question the validity of the eigenshape technique and discuss limitations of such an approach. Objections presented in this paper are applicable to a variety of other multivariable data reduction techniques as well.  相似文献   

13.
14.
A quantitative analysis was made of the spatial arrangement of 149explosion craters in the western rift of Uganda. A variety of methods demonstrate that the spatial pattern of the craters reveals significant structural patterns that have guided volcanism to the surface. It is shown that the east-west elements in the field affected location, and the main rift fault is resolved into two main components. Tentatively, a possible dextral transform fault is identified that affected the relative location of the two main zones of activity. Grouping techniques demonstrate that crater groups obey an exponential rank-size rule and allow a mapping of the craters into energy classes that reveals a concentric pattern of energy in the field. The effect of the topography on energy levels and crater size show that only topography greater than 11,000ft could have prevented all eruptive activity, but the smaller energies and craters are sensitive to height differences on the order of the height of the rift wall, about 1000ft. Total energy in each crater class size is roughly constant, and the field energy could create one or two single craters comparable in size to small central volcanoes.  相似文献   

15.
Chihuahueños Bog (2925 m) in the Jemez Mountains of northern New Mexico contains one of the few records of late-glacial and postglacial development of the mixed conifer forest in southwestern North America. The Chihuahueños Bog record extends to over 15,000 cal yr BP. An Artemisia steppe, then an open Picea woodland grew around a small pond until ca. 11,700 cal yr BP when Pinus ponderosa became established. C/N ratios, δ13C and δ15N values indicate both terrestrial and aquatic organic matter was incorporated into the sediment. Higher percentages of aquatic algae and elevated C/N ratios indicate higher lake levels at the opening of the Holocene, but a wetland developed subsequently as climate warmed. From ca. 8500 to 6400 cal yr BP the pond desiccated in what must have been the driest period of the Holocene there. C/N ratios declined to their lowest Holocene levels, indicating intense decomposition in the sediment. Wetter conditions returned after 6400 cal yr BP, with conversion of the site to a sedge bog as groundwater levels rose. Higher charcoal influx rates after 6400 cal yr BP probably result from greater biomass production rates. Only minor shifts in the overstory species occurred during the Holocene, suggesting that mixed conifer forest dominated throughout the record.  相似文献   

16.
Space spectral analysis of zonal (u) and meridional (v) components of wind and time spectral analysis of kinetic energy of zonal waves at 850 hPa during monsoon 1991 (1st June 1991 to 31st August 1991) for the global belt between equator and 40°N are investigated. Space spectral analysis shows that long waves (wavenumbers 1 and 2) dominate the energetics of Region 1 (equator to 20°N) while over Region 2 (20°N to 40°N) the kinetic energy of short waves (wavenumbers 3 to 10) is more than kinetic energy of long waves. It has been found that kinetic energy of long waves is dominated by zonal component while both (zonal and meridional) the components of wind have almost equal contribution in the kinetic energy of short waves. Temporal variations of kinetic energy of wavenumber 2 over Region 1 and Region 2 are almost identical. The correlation matrix of different time series shows that (i) wavenumber 2 over Regions 1 and 2 might have the same energy source and (ii) there is a possibility of an exchange of kinetic energy between wavenumber 1 over Region 1 and short waves over Region 2. Wave to wave interactions indicate that short waves over Region 2 are the common source of kinetic energy to wavenumber 2 over Regions 1 and 2 and wavenumber 1 over Region 1. Time spectral analysis of kinetic energy of zonal waves indicates that wavenumber 1 is dominated by 30–45 day and bi-weekly oscillations while short waves are dominated by weekly and bi-weekly oscillations. The correlation matrix, wave to wave interaction and time spectral analysis together suggest that short period oscillations of kinetic energy of wavenumber 1 might be one of the factors causing dominant weekly (5–9 day) and bi-weekly (10–18 day) oscillations in the kinetic energy of short waves.  相似文献   

17.
杨静勤 《江苏地质》1998,22(3):141-143
回顾了极谱分析工作的创始阶段,叙述了近50年来,极谱分析工作在有色金属、稀有元素矿石分析中的应用成果,介绍了极谱分析技术用于选矿、区域化探、标样研制等方面取得的新进展。  相似文献   

18.
Disk clusters are developed to represent the shape of granular materials more precisely (compared to circular particles) and to minimise excessive rolling. Investigating the behaviour of dynamic disk-based discontinuous deformation analysis (DDA) with disk clusters is very important to evaluate the applicability of disk-based DDA to dynamic problems in geomechanics. In this paper, the accuracy of disk-based DDA under dynamic conditions is studied by a comprehensive sensitivity analysis. The results obtained by disk-based DDA are compared with the analytical solutions of a disk cluster on an incline subjected to gravitational force only, and three different accelerations of increasing complexity with sinusoidal input functions as well as gravitational load. In this research, the effects of time step size and interface friction angles on the results are studied. Overall, most of the error for both velocity and displacement occurs at the beginning of the solution. With increasing friction angle, the initial perturbation of the solution increases in the case of sliding under gravitational force only, and decreases in the case of sliding under dynamic loads. This study shows that disk-based DDA predicts accurately the velocities and displacements derived with respect to the frictional resistance offered by the inclines.  相似文献   

19.
Compositional Data Analysis of Some Alkaline Glasses   总被引:1,自引:0,他引:1  
The approach to the analysis of compositional data involving log-ratio transformation of the data has not been generally adopted by researchers wishing to analyse such data. In the context of exploratory methods of multivariate analysis, such as principal components analysis, where the hope is to identify (cluster) structure in the data, this may be because traditional methods can produce more interpretable results than the log-ratio approach. After illustrating this with an example, circumstances under which the log-ratio approach performs poorly when traditional approaches work well are identified. Log-ratio analysis can be dominated by variables having low absolute presence and high relative variation that do not contribute to, and can obscure, structure in the data. Traditional methods can detect certain kinds of structure in the data that correspond to structure on a ratio scale, after a suitable redefinition of the composition. Since traditional methods often detect such structure more directly than log-ratio analysis it can be concluded that claims that the traditional analysis is inappropriate or meaningless are exaggerated. This conclusion is based on empirical experience rather than theoretical concerns. The arguments are illustrated using compositional data for alkaline glasses, but have more general application.  相似文献   

20.
地震多矢量属性相干数据体计算及应用   总被引:10,自引:1,他引:10  
在对相干分析算法研究的基础上,研究了一种新的相干分析算法-基于特征值结构的地震多矢量属性相干算法.该算法克服了单一属性相干算法的信息量不全的缺陷.既充分利用多属性的多方位信息,又要使其相互之间不发生矛盾,最大限度提高地质体边界的分辨率.经实际资料分析验证,结果非常理想.  相似文献   

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