江西德兴斑岩铜矿田断裂分形研究

A Study of Fractal Dimension of the Fracture System in the Dexing Porphyry Copper Orefield, Jiangxi

本文将分形几何学的原理和方法应用于江西德兴斑岩铜矿田三组断裂系统的二维平面分布特征研究,发现在研究的标度范围内不仅具有统计自相似性,而且不同矿区子区域具有不同的分维数D值。矿化岩体产出部位分维值明显高于整个矿田分维值,NE向断裂体系分维值略高于WNW向体系分维值。结合断裂产状、时代、穿切关系与岩体侵入部位对比可知,分维值越高,越有利于矿床形成,矿床规模也越大,其中NE向和WNW向断裂体系起主导控矿作用。

Through the application of the principles and methods of fractal geometry to the study of fractal characteristics of the two-dimensional distribution of three different fracture systems in the Dexing porphyry Cu orefield, the authors found that these fracture systems not only possess the statistical self-similar character in the scale extent studied, but also h,v/e different D values of fractal dimension in different ore districts and fracture systems. As a result of this study, the D values of fractal dimension in the sub-range of mineralized porphyries are higher than that of the whole orefield, and that of the NE fracture system is slightly higher than the WNW fracture system. The characteristic distribution of D values coupled with comparison of the attitudes, penetration relationships and ages of different fracture systems with the location of porphyry Cu ore bodies indicates that the higher the D value, the more favorable the conditions of Cu ore formation and larger the deposit size and that the NE- and WNW-trending fracture systems play an important controlling role in ore-forming processes.