黔西南戈塘-海子地区金矿控矿因素分析与成矿模式探讨

Analysis on ore-controlling factor and metallogenic model of gold deposits in Getang-Haizi area,Southwest Guizhou

在对区内构造性质及组合特征实地调查研究的基础上,系统总结区内“断裂型”、“界面型”、“土型”三类型金矿赋矿地质体空间产出特征及分布规律,进而提出NE向海马谷断层及配套的次级断裂为戈塘地区金矿成矿流体的主要通道,戈塘背斜为成矿前构造,对后期的成矿流体运移起到汇聚作用,中上二叠统(P_(2)m,P_(3)l)之间的岩溶不整合面为区内金矿体主要就位空间。结合稀土元素、硫同位素、包裹体研究成果以及区域航磁、重力特征,认为区内金矿为与深源岩浆活动有关、受NE向大型逆冲断层及其配套构造联合控制,具有“断裂+多层界面”矿体空间就位特征的中低温热液型金矿床。

Based on the field investigation and study on structural properties and assemblage characteristics in the area,this paper systematically summarizes the spatial occurrence characteristics and distribution regularity of ore-bearing geological bodies of three types of gold deposits in the area,i.e."fault type","interface type"and"soil type".Furthermore,it is proposed that the NE-trending Haima Valley fault and its supporting secondary faults are the main channels of gold ore-forming fluids in the Getang area.The Getang anticline is a pre-metallogenic structure,which plays a role in the migration of later ore-forming fluids.The karst unconformity between the Middle-Upper Permian(P_(2)m,P_(3)l)is the main place for gold orebodies in the area.Combined with the research result of rare earth elements,sulfur isotopes,inclusions and regional aeromagnetic and gravity characteristics,it is considered that the gold deposit in the area is a medium low temperature hydrothermal type gold deposit related to the deep source magmatic activity,controlled by the large NE thrust fault and its supporting structures,and has the spatial location characteristics of"fault+multi-layer interface"orebody.