二级套合结构实验变差函数的几何拟合

叠加地球化学场表现为各地球化学元素的变差函数具有双重套合结构。拟合实验交差函数是分解叠加地球化学场的关键。本文依据地球化学场自相关与自相似的内在联系,提出用多标度分形谐方法拟合具有二级套合结构的实验交差函数。     

多重分形在海积软土微观结构研究中的应用

本文将多重分形谱引入到土微观结构分形研究中,对天津市滨海新区三个不同地点海积软土原状样及不同固结压力后土中孔隙的多重分形特征进行研究,从多重分形的角度对孔隙的不均匀性进行定量描述,并建立孔隙多重分形谱各特征参数与荷载之间的关系.结果表明三个地点的海积软土孔隙多重分形特征存在差异.     

Seismicity pattern of the Betic Cordillera(southern Spain) derived from the fractal properties of earthquakes and faults

Several studies on earthquake occurrence and associated faulting have demonstrated that both phenomena have a scale-invariant behavior which can be analyzed by means of a set of non-integer dimensions(Dq) describing their fractal properties and the calculation of multi-fractal spectra.It is the case that the behavior of these spectra is asymptotic at the ends of the variation interval of q,which is a real number that enters into the definition of the partition function of the dataset.The difference between the extreme values,called multi-fractal spectrum slope,is used to investigate the heterogeneity of the spatial distribution of earthquakes and fault systems.In this paper we focus on the Betic Cordillera,southeastern Spain,which is commonly considered the contact between the Eurasian and African plates and has an important seismic activity in the context of the Iberian Peninsula.Some of the most conspicuous Iberian earthquakes,such as the 1829 mb6.3 Torrevieja and the 1884 mb6.1 Alhama de Granada earthquakes occurred in this mountain range and both reached intensity X.The present work implies a new analysis based on the slope of multi-fractal spectra and referred to the historical seismicity of the region,specifically b-value(frequency distribution of earthquakes respect to magnitude),epicentral location,seismic energy and faulting.On this basis we propose a seismotectonic zonation that is contrasted with the stress state and the geodynamical evolution of the Betic Cordillera.     

北山花岗岩深部节理间距分布多重分形研究

岩体节理几何特征定量描述是岩体力学性质和渗透性研究的基础,更是核废料处置库场址筛选和评价过程的主要内容。基于甘肃北山高放废物深地质处置库预选区BS17、BS18和BS19钻孔岩芯节理数量修正数据,针对节理间距建立了类负指数分布数学统计模型,进一步应用于RQD体系定量评价深部岩体完整性,通过与RID体系对比验证了概率模型的可靠性。指出节理数量-间距关系具有明显的分段线性特征,分维数随着间距增大而增大。确定了节理间距-数量关系符合尺度律,得出了数量与间距关系的多重分形特征。进一步分析了数量与埋深的多重分形特征,初步实现了岩芯节理的定量描述。验证了多重分形谱可以很好地统计分形维特征,尤其是节理几何形状及分布特征。该研究结果可为实现基于钻孔岩芯节理几何特征数据的深部岩体节理三维网格模拟提供参考。     

孕震物理过程探索

本文根据非线性科学观点，从多分形、自组织临界现象和浑沌动力学等三个方面综述了地震孕育过程的动力学演化特征及其系统的不稳定性问题。     

合肥市大兴地区土壤中镉元素的空间分布的多维分形特征研究

土壤中cd元素空间分布的研究是土壤科学的重要内容,也是土壤环境污染评价与防治的重要依据。空间变异研究中最为常用的克里格插值法能够较为精确的进行空间估值,但由于它的低通滤波性,使得对于较高数值的异常点往往不能正确估计。而异常区域的元素分布状况恰是环境污染评价与防治最为关注的。因此,本文采用多维分形地统计学方法,对大兴地区的镉元素进行了空间插值分析。结果表明,该方法能较好的反映cd元素的空间分布奇异性。     

岩石地球化学异常下限的确定方法对比——以云南思姑锡矿区为例

文章以云南思姑锡矿区周边岩石的X荧光化探样品中的Sn元素为研究对象,分别采用传统统计法、勘查数据分析法和多重分形法确定异常下限,并对各方法在研究区的使用效果进行了对比。勘查数据分析法圈定的异常比已知矿床、矿化带范围小,异常较为分散;传统统计法圈定的异常与已知矿床、矿化带范围基本吻合,且较为连续,但漏掉很多弱小异常;多重分形法圈定的异常与已知矿床、矿化带范围几乎完全吻合,异常连续性好,没有漏掉弱小异常,并圈定出一些未知的异常区域,为下一步矿区外围找矿工作提供了重要参考。     

应用奇异值分解(SVD)技术提取西铜石金矿田致矿重力异常

基于MATLAB平台编制的奇异值分解(SVD)程序有效地应用于铜石金矿田1:50000重力数据分解.首先,利用奇异值分解将重力数据分解为一系列的特征值空间;然后运用多重分形技术确立反映不同层次控矿因素的特征空间值的临界值,最后将这些具有不同控矿因素特征的特征空间值按一定的规则进行数据重构.结果获取三幅刻画不同尺度控矿因...     

应用奇异值分解与二维经验模型分解提取金矿化致矿重力异常

奇异值分解(singular value decomposition,SVD)和二维经验模型分解(bi-dimensional empirical mode decomposition,BEMD)2种方法用于鲁西铜石金矿田的金矿化致矿重力异常提取.通过对比研究得出如下结论:①基于重力数据,由BEMD和SVD 2种方法获...     

Multi-fractal Behaviors of Relative Humidity over China

The multi-fractal behaviors of relative humidity over China are studied using the multi-fractal detrended fluctuation analysis (DFA) method. Three multi-fractal parameters (the spectrum width Δα, the asymmetry Δα as , and the long-range correlation exponent α 0 ) of the singularity spectrum are introduced to quantify the multi-fractal behaviors. The results show that multi-fractality exists in daily humidity records over most stations in China and is mainly due to the broad distribution of the probability density of the sequence values. Strong multifractal behaviors over some stations in the Yunnan, Guangdong, and Inner Mongolia provinces are obvious. These behaviors are mainly caused by different longrange correlations between large and small fluctuations. The asymmetry of the singularity of relative humidity records is weak, except for a small number of stations in the far east and west of China, where the singularity spectrum is left-skewed. Finally, the long-range correlations in North China are stronger than those in South China, which indicates better predictability in North China. By studying the parameters of the multi-fractal spectrum, various data of long-range power law correlations of the relative humidity records are obtained, which may provide theoretical support for climate prediction.