广西贺州水岩坝矿田断裂构造分形特征分析

文章基于盒计维数法对水岩坝矿田断裂构造进行了系统的定量分析,结果显示矿田内不同尺度的断裂构造具有良好的自相似性。其中,断层的分维值为1.3475;矿田中部的烂头山矿床节理和手标本微裂隙的平均分维值分别为1.7841和1.3310;在子区分维高次趋势图上,分维高值区总体延伸趋势为北西向,与矿田断层构造总体展布趋势相吻合。平面上,烂头山矿床正常围岩微裂隙、蚀变围岩微裂隙和矿(化)体微裂隙的平均分维值分别为1.2097、1.3310和1.8622,表明矿化程度的高低与其微裂隙分维值的大小成正比;垂向上,烂头山矿床露头节理平均分维值随高程的升高而增大,显示烂头山矿床具有含钨石英脉型的"五层楼"模式特点。此外,水岩坝矿田内已知矿床(点)均位于分维高值区,说明分维值的高低与已知矿床(点)的分布具有耦合性。

Fractal characteristics analysis of fractures in Shuiyanba ore field of Hezhou, Guangxi

A systematic quantitative analysis of fault structures in the Shuiyanba ore field were conducted on the basis of the box-counting dimension method. It is found that the faults of different scales in the Shuiyanba ore field have good self-similarity. The fractal dimension of faults is 1.3475, the average fractal dimensions of micro-cracks of joints and hand specimens in the Lantoushan deposit of central ore field are 1.7841 and 1.3310 respectively; in the figure of subinterval high fractal dimension, the fractal dimension of the overall extension of the high value area trends northwest, the overall trend of fault structures and the ore field is consistently spread. In the plane, the average fractal dimensions of normal rock micro-fissures, micro-fractures of altered wall rock and ore or mineralized bodies in the Lantoushan deposit are 1.2097, 1.3310 and 1.8622 respectively, suggesting that the level of mineralization and the size of fractal dimension crack are proportional. In the vertical direction, the average fractal dimension of outcrop joints in the Lantoushan deposit increases with increasing elevation, indicating that the Lantoushan deposit is characterized by tungsten-quartz vein type "five-storey" model. In addition, the known mineral deposits (ore spots) in the Shuiyanba ore field are located in the high value fractal dimension area, implying that the level of the fractal dimension is coupled with the known deposits (ore spots) in spatial distribution.