陕西省略阳县干河坝金矿地质特征及矿床成因探讨

Geological Characteristics and Genesis of Ganheba Gold Deposit in Lueyang County,Shaanxi Province

干河坝金矿床是南秦岭南段勉略康构造混杂岩带内属受岩相和构造双重控制的构造蚀变岩型金矿床。该矿床的矿体集中产于古生界泥盆系金家河岩组金家河千枚岩与乔子沟火山岩的岩性—构造接触带附近,多呈似层状、透镜状。为进一步探讨该矿床成因,通过对矿床成矿地质特征、地球化学背景及硫同位素的系统研究,认为①该矿床的赋矿层位就是其初始矿源层;②经区域变质变形和多期构造活动,初始矿源层中的成矿物质活化、迁移,在近EW向张性裂隙中充填、沉淀而富集成矿。

Ganheba gold deposit is a tectonic altered rock type gold deposit controlled by both lithofacies and structure in the Mianluekang tectonic melange belt of the southern section of the southern Qinling mountains.The ore bodies are concentrated in the vicinity of the lithological-structural contact zone between the Ginjihe phyllite and the Qiaozigou volcanic rocks of the devonian jinjihe formation in the Paleozoic.The ore-forming geological characteristics,geochemical background and sulfur isotopes of the ore deposit are summarized.After regional metamorphism,deformation and multi-stage tectonic activities,the ore-forming materials in the source layer are activated and migrated,and the ore-forming materials are filled and deposited in the EW-trending tensile fractures to enrich the ore-forming process.