CAJ | 학술논문

阿克希克铁金矿床位于准噶尔北缘，矿体呈似层状、脉状、透镜状赋存于南明水组火山岩及凝灰岩的接触带上。围岩蚀变不发育，主要为硅化、绢云母化、绿泥石化、黄铁矿化、碳酸盐化等。矿床的形成经历了火山沉积期和热液期，铁矿化主要形成于火山沉积期，金矿化主要形成于热液期。火山沉积期石英以发育液体包裹体和少量含CO2包裹体为特征，热液期石英以发育含CO2和碳质(CH4和C4H6)包裹体为特征。火山沉积期成矿流体为中温(集中于180~320℃)、低盐度(集中于6~10 wt%NaCleq)、中-低密度(0.59~0.98 g/cm3)的NaCl-H2O-CO2体系。热液期成矿流体为中温(集中于220~320℃)，低盐度(集中于2~10 wt%NaCleq)，中-低密度(0.55~1.03 g/cm3)的NaCl-H2O-CO2-CH4型流体。火山沉积期石英的δDSMOW为-129.9‰~-97.9‰，δ18OSMOW值介于7.9‰~12.3‰，δ18OH2O值为-2.6‰~4.4‰，推测成矿流体为海水与岩浆水的混合。热液期石英的δDSMOW介于-129.8‰~-102.6‰，δ18OSMOW值介于11.2‰~16.1‰，δ18OH2O变化于3.1‰~7.4‰，推测成矿流体为变质水混合深循环的大气降水。结合矿床地质特征、流体成分和性质，本文认为热液期金矿化与CO2-CH4流体有关。
아극희극철금광상위우준갈이북연，광체정사층상、맥상、투경상부존우남명수조화산암급응회암적접촉대상。위암식변불발육，주요위규화、견운모화、록니석화、황철광화、탄산염화등。광상적형성경력료화산침적기화열액기，철광화주요형성우화산침적기，금광화주요형성우열액기。화산침적기석영이발육액체포과체화소량함CO2포과체위특정，열액기석영이발육함CO2화탄질(CH4화C4H6)포과체위특정。화산침적기성광류체위중온(집중우180~320℃)、저염도(집중우6~10 wt%NaCleq)、중-저밀도(0.59~0.98 g/cm3)적NaCl-H2O-CO2체계。열액기성광류체위중온(집중우220~320℃)，저염도(집중우2~10 wt%NaCleq)，중-저밀도(0.55~1.03 g/cm3)적NaCl-H2O-CO2-CH4형류체。화산침적기석영적δDSMOW위-129.9‰~-97.9‰，δ18OSMOW치개우7.9‰~12.3‰，δ18OH2O치위-2.6‰~4.4‰，추측성광류체위해수여암장수적혼합。열액기석영적δDSMOW개우-129.8‰~-102.6‰，δ18OSMOW치개우11.2‰~16.1‰，δ18OH2O변화우3.1‰~7.4‰，추측성광류체위변질수혼합심순배적대기강수。결합광상지질특정、류체성분화성질，본문인위열액기금광화여CO2-CH4류체유관。
The Akexike Fe-Au deposit on the northern margin of the Junggar Basin occurs in the contact zone between volcanic rocks and tuffs of the Nanmingshui Formation. The orebodies are podiform, veined, and lenticular in form. The deposit has expereinced silicification, sericitization, chloritization, pyritization and carbonatization. Field evidence and petrographic analysis indicate two periods of metallogenesis:the volcanic-sedimentary period associated with the development of Fe mineralization and the hydrothermal period associated with Au mineralization. Liquid- and a few CO2- rich inclusions characterize the volcanic-sedimentary period, whereas CO2- and carbon (CH4 and C4H6)-rich inclusions characterize the hydrothermal period. Volcanic-sedimentary period had NaCl-H2O-CO2 fluids with moderate temperature (major Th of 180-320℃), low salinity (mainly 6-10 wt% NaCleq), and modereate to low density (0.59-0.98 g/cm3). Hydrothermal period has NaCl-H2O-CO2-CH4 fluids with moderate temperature (major Th of 220-320℃), low salinity ( mainly 2-10 wt%NaCleq), and moderate to low density (0.55-1.03 g/cm3). Stable isotope analysis of quartz yielded values of-129.9‰to-97.9‰forδD, 7.9‰to 12.3‰forδ18OSMOW, and-2.6‰to 4.4‰forδ18Ofluid, indicating that the ore-forming fluids were magmatic fluids mixed with seawater.δD,δ18OSMOW, andδ18Ofluid values of the hydrothermal period are-129.8‰--102.6‰, 11.2‰-16.1‰, and 3.1‰-7.4‰, respectively, indicating that the ore-forming fluids were metamorphic water mixed with deeply circulated meteoric water. Combined with geological characteristics and fluids composition, the authors hold that Au mineralization of hydrothermal period was closely associated with CO2-CH4 fluids.