新疆阿尔泰南缘萨热阔布—铁木尔特一带的矿床均赋存于下泥盆统康布铁堡组的变质岩系中。早泥盆世的海相火山形成了Zn-Pb(Cu)矿化,晚泥盆世-早石炭世的碰撞造山相应形成了Cu-Au石英脉矿化;前者以铁木尔特VMS型Zn-Pb(Cu)矿床为代表,后者以造山型萨热阔布金矿为代表,与造山有关的脉状矿化还叠加在铁木尔特等VMS矿床中。通过对比两类矿化的稳定同位素特征,结合矿化的变形变质和流体包裹体特征,研究了成矿物质、成矿流体来源和矿床成因。萨热阔布金矿主成矿阶段硫化物石英脉和铁木尔特Zn-Pb(Cu)矿床中晚期发育的含黄铜矿石英脉中均富含碳质(CO2-CH4-N2)流体包裹体,可能与碰撞造山的热液流体作用有关。铁木尔特Zn-Pb(Cu)矿床中代表VMS期的浸染状矿石中硫化物δ34S为-26.46×10-3~-19.72×10-3,硫主要来源于海水硫酸盐的无机还原和细菌还原作用;而代表后期叠加改造的脉状矿化硫化物值与萨热阔布金矿床硫化物石英脉中δ34S值接近,硫主要来源于造山过程中的深源流体。萨热阔布金矿床硫化物石英脉和铁木尔特Zn-Pb(Cu)矿床晚期含黄铜矿石英脉的δDH2O值和δ18OH2O值,均反映了碰撞造山期热液与岩浆活动和变质作用有关。萨热阔布金矿硫化物石英脉中碳质流体包裹体CO2体系中δ13C为-21.15×10-3~-7.51×10-3,CH4体系的δ13C为-34.11×10-3~-28.38×10-3;铁木尔特Zn-Pb(Cu)矿床含黄铜矿石英脉中碳质包裹体测得的δ13C为-8.02×10-3~-6.99×10-3,δ13C特征与海相火山沉积无关,具岩浆源或深部源的特点。
The Sarekoubu——Tiemurte deposits in southern Altay of Xinjiang occurred in metamorphic rocks of Lower Devonian Kangbutiebao Formation.The Zn——Pb(Cu) mineralization related to the Early Devonian marine volcanic deposition Zn——Pb(Cu) and the late Devonian——Early carbonifeneus quartz veins mineralization related to the collisional orogeny.The former is represented by the VMS type Tiemurte Zn——Pb(Cu) deposit,and the latter by the orogenic type Sarekoubu gold deposit,and the vein mineralization related to orogeny superposed in the VMS deposit.Based on the study and comparison of stable isotope characteristics of the two types of mineralization,combined with the deformation and metamorphism of mineralization and fluid inclusions,the authors discuss the metallogenic minerals,fluids and ore genesis.The carbonic(CO2-CH4——N2) fluids inclusions are widely developed in the sulfide quartz veins of the Sarekoubu deposit and the Cu-bearing quartz veins in late stage of Tiemurte deposit,indicating that the carbonic fluid inclusions are related to the hydrothermal fluid of collision orogeny.In the Tiemurte Zn——Pb(Cu) deposit,the δ34S values of sulfides in VMS ores range from-26.46×10-3 to-19.72×10-3,indicating that the sulfur mainly from the inorganic reduction and bacterial reduction of seawater sulfate.The δ34S of sulfides from late superimposed veins is closed to the δ34S values of sulfides in Sarekoubu gold deposit,indicating a deep source of sulfur in the ores.The δDH2O and δ18OH2O in the Sarekoubu gold deposit and Tiemurte Zn——Pb(Cu) deposit indicate the fluids in collision orogeny were related with the magmatic activity and metamorphism.δ13C values of CO2 in carbonic inclusions range from-21.15×10-3 to-7.51×10-3,and those of CH4 range from-34.11×10-3 to-28.38×10-3 in Sarekoubu gold deposit.Whereas,δ13C values from inclusions in late Cu-bearing quartz veins in the Tiemurte range from-8.02×10-3 to-6.99×10-3,δ13C show a deep source or magma source that is