河北大西沟金矿地质特征与成因探讨

Discussion on Geological Characteristics and Genesis of Daxigou Gold Deposit in Hebei

大西沟金矿床是冀北地区近几年来新发现的重要金矿床之一。在前人工作的基础上,通过对勘探资料的深入研究和野外观察,初步确定该矿床主要为蚀变岩型和石英脉型金矿床,规模为中型,金矿化主要与硅化、黄铁矿化和钾化有关,矿体严格受NEE向断裂构造破碎带控制。通过围岩与矿体的微量元素、硫同位素、氢氧同位素的分析,推测其成矿物质来源于红旗营子群变质岩及岩浆岩,成矿流体既有岩浆热液水,也有大气降水,岩浆为矿体提供热源,认为大西沟金矿是一个典型的中浅成中低温岩浆热液型金矿床。

Daxigou gold deposit is one of the important gold deposits found recently in the northern Heibei Province. Based on previous work, combined with further study of the exploration data and the field survey to the region, it is confirmed that Daxigou is a quartz vein-altered rock type gold deposit, with middle scale, mineralization are mainly related to silicification, pyritized and potassium alteration, ore-bodies are directly controlled by NEE-trending fault structure zones. According to analysis on surrounding rock and trace elements, S isotope and H, 0 isotope of the orebody, we conclude that the ore-forming materials are originated from metamorphic rocks and magmatic rocks of Hongqiyingzi Group, the fluid is from magmatic water mixed with meteoric water, and heating of ore bodies comes from magma, so we consider the deposit is a typical medium-low depth and medium-low temperature magmatic hydrothermal type gold deposit.