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1.
趋势分析法作为场分离的一种方法,当地形情况复杂、测区面积较大时,往往很难达到场分离的要求。文章通过改变多项式数学模型的阶次,选择最优的多项式数学模型进行趋势分析。通过对剖面趋势分析和曲面趋势分析的对比得知,在同一地质模型上剖面趋势分析效果较曲面趋势分析效果好,由此运用切割法将叠加异常数据直接截取,获得多个剖面进行趋势分析,再由剖面趋势分析得到曲面趋势分析。实验结果表明趋势分析效果理想,能达到场分离的要求。  相似文献   

2.
岩相剖面的定量历史沉积学分析是以动力沉积学分析为基础、以数学地质为方法、以计算机为工具的定性-定量分析法.它主要包括马尔科夫链模型中的转移概率矩阵分析,置换分析,极限概率和马尔科夫链的首达时间分析,熵分析和时间序列分析,本文侧重从地质学的角度阐述了它们的原理和方法。  相似文献   

3.
对岩土工程数值分析的几点思考   总被引:6,自引:1,他引:5  
龚晓南 《岩土力学》2011,32(2):321-325
首先,介绍了笔者对我国岩土工程数值分析现状的调查结果及分析,然后,分析了采用连续介质力学分析岩土工程问题的关键,并讨论分析了岩土本构理论发展现状,提出对岩土本构理论发展方向的思考,最后对数值分析在岩土工程分析中的地位作了分析。分析表明,岩土工程数值分析结果是岩土工程师在岩土工程分析过程中进行综合判断的重要依据之一;采用连续介质力学模型求解岩土工程问题的关键是如何建立岩土的工程实用本构方程;建立多个工程实用本构方程结合积累大量工程经验才能促使数值方法在岩土工程中由用于定性分析转变到定量分析。  相似文献   

4.
小波分析的应用现状及展望   总被引:20,自引:0,他引:20  
小波分析具有多分辨分析的特点,在时频两域都具有表征信号局部特征的能力,是一种窗口大小固定不变,但其形状可以改变的时频局部化分析方法。本文从介绍小波分析的发展简史开始,简述小波分析的基本原理,分析和总结小波分析在地球物理勘探、信号和图像处理中的最新应用成果。讨论小波分析目前应用中存在的主要问题,并展望小波分析一些有前景的应用领域。   相似文献   

5.
基于粒子群优化的岩土工程反分析研究   总被引:11,自引:0,他引:11  
高玮 《岩土力学》2006,27(5):795-798
岩土工程优化反分析本质上看是一个典型的复杂非线性函数优化问题,采用全局优化算法是解决这个问题的理想途径,但由于优化反分析中多次调用正分析的特点使得整个算法的计算效率很低。为了提高优化反分析的计算效率,把一种计算效率更高的新型仿生算法--粒子群优化引入岩土工程反分析领域,提高反分析的计算效率。在此基础上,结合有限元数值分析技术,提出了一种新的岩土工程优化反分析算法--粒子群优化反分析。并通过一个简单算例验证了该法的有效性。  相似文献   

6.
三维矿产资源潜力评价中GIS空间分析的应用研究   总被引:1,自引:0,他引:1       下载免费PDF全文
赵增玉  潘懋  郭艳军 《江苏地质》2012,36(4):366-372
三维矿产资源潜力评价是近年来随着三维地学建模技术的发展而提出的,为大比例尺矿产预测、危机矿山中深部找矿提供了新的思路和技术手段,而三维空间分析则是在三维地学模型基础上的进一步分析和应用。介绍了三维矿产资源潜力评价的概念、流程以及目前常用的GIS空间分析手段。针对三维矿产资源潜力评价,分别从成矿分析、控矿信息提取、控矿信息综合和评价结果分析4个方面阐述三维查询分析、三维缓冲分析和三维叠加分析等不同三维空间分析手段的应用。通过安庆铜铁矿实例,展示了该矿床三维矿产资源潜力评价中GIS空间分析的应用。  相似文献   

7.
刘忠胜  段英楠  邵明辰 《吉林地质》2012,31(1):107-108,119
通过对影响分析结果质量的消解方式、称样量、消解器皿及环境等因素进行分析,并采取相应措施,保证了分析结果的准确性、检出限,提高分析数据的重现性。  相似文献   

8.
地质分析技术产生的数据是进行地质科学研究和矿产资源、地质环境评价的重要基础,是发展国土资源地质调查事业和地球科学的重要技术支撑。中国地质事业已经得到了空前的发展,地质分析文献迅速增加,迫切需要对文献进行整理、加工、综合、评价。为了解当前中国地质分析技术在各领域的应用状况和获得的成果,对国内科研人员20年来发表的地质分析应用类评述性论文作一评介,内容联系当今全球地质分析技术发展的新趋势,主要包括标准物质与标准方法,岩石矿物分析,地球化学调查(区域地球化学、多目标地球化学和生态地球化学调查)、地球化学填图样品分析,海洋地质样品分析,现场分析,贵金属分析,化学物相与元素形态分析,水分析,能源矿产和环境样品分析,稳定同位素和同位素地质年代学技术与应用10项分析技术领域取得的研究成果。阐述了国内地质分析技术新应用领域的进展、动态和发展前景。  相似文献   

9.
以基于离轴积分腔输出光谱(OA-ICOS)原理的液态水同位素分析仪为例,通过开展记忆效应分析实验和标定方法分析实验,分析了氢氧同位素测试分析中的记忆效应表现特征,讨论了记忆效应对测试结果的影响程度,探讨了记忆效应标定方法。研究结果表明:采用常规运行方法进行氢同位素测试分析时,记忆效应是明显存在的,而进行氧同位素测试分析时,记忆效应表现并不明显;采用常规运行方法进行氢、氧同位素测试分析,基本可以达到液态水同位素分析仪的保证精度;测针次数的增加,对于提高氢、氧同位素的测试分析精度具有有效作用;选择与待测样品δ值最为相近的3个标样进行测试分析和标定处理工作,可达到提高测试效率、节省测试成本、提高测试精度的目的。  相似文献   

10.
目前的观测系统优化设计方法主要以理论的CMP面元属性分析为主,按照炮检距、覆盖次数、方位角等的分布均匀性进行分析,以CRP面元属性分析、地震照明分析、叠前分析作为辅助性分析手段,但这些方法无法对复杂构造区不同类型观测系统的实际地震资料成像能力进行分析.基于此,这里提出了基于实际地震数据驱动的观测系统评价方法:首先从工区...  相似文献   

11.
According to the rules accepted by the Commission on New Minerals, Nomenclature and Classification, International Mineralogical Association, the definition of a new mineral species within the eudialyte group should be based on the general crystal chemical principle of the predominance of a new element at one or several key sites. To date, 25 minerals of the eudialyte group have been approved in line with this recommendation. Additionally, 50 samples (including potential new species of the eudialyte group) have been investigated using IR spectroscopy and X-ray diffraction. The new data require the modification and complementation of the current systematics of the eudialyte group. The eudialyte-type structures contain unique fragments that involve species-forming key sites. The crystal chemical classification that develops in this study is based on the hierarchical principle that takes into account the following features (listed in order of their lowering classification rank):
  1. simple or modular character of the crystal structure and value of c parameter (about 30 and 60 Å for 12- and 24-layer minerals, respectively)
  2. symmetry determined by cation ordering in the octahedral ring, i.e., the possibility of dividing site M(1) into M(1a) and M(1b)
  3. the distribution of different components into five M(2) square-based sites
  4. the water content (subdivision of the eudialyte-group minerals into low-and high-hydrous species with Na > (H2O + H3O) and Na < (H2O + H3O), respectively.
The 12-layer minerals are subdivided into eudialyte- and oneillite-type species. The further subdivision of these two types into subtypes is based on the predominance of octahedra, tetrahedra, or vacancies at sites M(3) and M(4) in the centers of nine-membered Si,O-rings and different combinations of these variants. Both type and subtype terms are used here in the crystal chemical sense. Among 24-layer minerals, the first subdivision is based on the degree of hydration; the second subdivision into subtypes takes into account combinations of predominant components (Zr + Zr, Ti + Ti, or Zr + Ti) in Z octahedra of different modules (floors). Various eudialyte-group minerals that belong to different crystal chemical taxons are briefly characterized.  相似文献   

12.
河流分类体系研究综述   总被引:3,自引:0,他引:3       下载免费PDF全文
简要阐述河流分类的目的和方法,重点对基于地貌、水文、生态、价值的分类体系进行了回顾,按照时间顺序说明了各种分类体系的发展过程。河流分类体系不断走向系统与综合,体现在从单要素到多要素、从定性到定量、从结构到过程、从单尺度线状河流到多尺度等级系统,以及从自然系统到包含社会价值。随着河流生态学实验及理论的发展、多学科的合作以及多尺度数据源条件的改善,具有预测功能的分类体系将逐步取代描述性的分类体系。国际河流分类体系的研究成果对于我国多类型河流的生态恢复与管理具有重要的借鉴意义。  相似文献   

13.
A listing of the recognized types of uranium mineralization shows nineteen determinable types out of which only six can be classified as of economic significance at present: Oligomictic quartz pebble conglomerates, sandstone types, calcretes, intra-intrusive types, hydrothermal veins, veinlike types. The different types can be genetically related to prevalent geological environments, i. e. 1. the primary uranium occurrences formed by endogenic processes, 2. the secondary derived from the primary by subsequent exogenic processes, 3. the tertiary occurrences are assumed to be formed by endogenic metamorphic processes, however, little is known about the behaviour of the uranium during the metamorphosis and thereby the metallogenesis of this tertiary uranium generation is still vague. A metallotectonic-geochronologic correlation of the uranium deposits shows that a distinct affinity of the uranium exists to certain geologic epochs: to the Upper Archean — Lower Proterozoic, to the Hercynian and in a less established stage: to the Upper Proterozoic.  相似文献   

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16.
着重讨论了金刚石微粉的界定问题,并介绍了前苏联、DeBeers公司、瑞士RudolfSpring公司的金刚石微粉产品品种,同时还对金刚石超细微粉作了简要说明。  相似文献   

17.
An attempt is made at compiling an artificial classification scheme for cuticle fragments of undetermined systematic affinity, using Early Permian and Late Triassic dispersed cuticles from the Pechora Basin. A nomenclature is suggested which reflects the character of the stomatal apparatus. Five new form genera, each with one species, are described. --D.C. McGregor.  相似文献   

18.
Space debris, here referring to all non-operating orbital objects, has steadily increased in number so that it has become a potential barrier to the exploration of space. The ever-increasing number of space debris pieces in space has created an increasingly threatening hazard to all on-the-orbit spacecraft, and all future space exploration activities have to be designed and operated with respect to the increasing threat posed by space debris. Generally, space debris is classified as large, medium and small debris pieces based on their sizes. The large debris piece is easily catalogued, but medium to small debris pieces are very difficult to track and also quite different in damage mechanisms from the large ones. In this paper, a scheme of chemical classification of space debris is developed. In our scheme, the first-order classification is employed to divide space debris into two groups: natural  相似文献   

19.
The authors, noting shortcomings in previous classifications of ore bodies and ore fields, present a detailed system of distinguishing postmagmatic occurrences, further developing A. V. Korolev's 1954 system. That system noted three main groups, conformable, intersecting and contact bodies, subdivided into 11 classes and 18 types of ore bodies. The present classification divides all fields into two main groups: those in mobile zones and those in platforms. The resulting 26 categories are further subdivided to distinguish containing formations. The authors stress the need for such distinction. Examples are given for each deposit, including name of ore field, country where located and type of metal. Special attention is given to the occurrences of ores in Precambrian formations.–A. Eustus.  相似文献   

20.
根据耦合作用实现方式的不同,将温度-渗流-应力耦合作用分为“力学”耦合和“参数”耦合两大类,“力学”耦合通过场之间的某种力学作用或过程实现,而“参数”耦合则通过场的控制参数的变化而体现出来。  相似文献   

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