西南“三江”成矿带北段区域成矿断裂信息定量化分析

"三江"北段成矿带是中国著名的"三江"铜多金属巨型成矿带的北延部分,构造上属特提斯巨型成矿域的重要组成部分,区域成矿条件极为优越。区内矿床主要为斑岩型铜钼矿床和热液型铅锌矿床,成矿主要受断裂构造的控制,定量分析成矿断裂信息对于指明区域找矿方向至关重要。以GIS技术为平台,采用断裂等密度、断裂中心对称度、断裂优益度、断裂交点数、断裂频数等参数定量地分析区域断裂信息,从中提取区域主干断裂发育区和次级断裂发育区。区域成矿特征表明,本区矿床沿区域主干断裂成带状分布,而次级断裂发育区为主要的矿床赋存区。通过定量分析发现,本区2个主要矿集区之间的扎青乡地区存在一个成矿断裂信息异常高值区,认为是本区今后找矿的有利区域。

he quantitative analysis of regional metallogenic fault in the northern segment of the Sanjiang metallogenic belt, southwestern China

The northern segment of the Sanjiang metallogenic belt is the north-extension part of the Sanjiang copper polymetallic super-large metallogenic belt, which is one of the most important part of Tethys-Himalaya metallogenic domain on structure, of which with favorable regional metallogenic conditions. The porphyry copper (molybdenum) deposits and lead-zinc deposits are mainly deposits in the Sanjiang metallogenic belt. The mineralization is mainly controlled by fault structures. So the quantitative analysis of metallogenic faults is the most important to point out the regional prospecting direction. The authors used fault structure iso-density, centre symmetry of fault structure, advantageous of fault structure, intersection site of fault structure, fault structure frequency and so on to analysis regional faults quantitatively on GIS techniques flat, and to extract regional main faults and second-order faults. The research results of regional mineralization characteristics show that the deposits have the characteristics of zonal distribution along the regional main faults, and the main deposits mainly occur in the development area of second-order faults. The research results of quantitative analysis show that the high value anomaly area of which between two main ore clustering areas, namely Zhaqing zone is the favorable orientation in the future in study area.