CAJ | 학술논문

色那金矿是西藏多龙矿集区内发现的一个浅成低温热液型金矿点，其成岩成矿时代一直缺乏精确的年代学约束。对该金矿石英二长闪长岩进行了 LA ICP MS 锆石 U Pb 定年、主微量元素分析和Sr Nd 同位素组成研究，首次获得了多龙矿集区色那金矿赋矿岩石的成岩时代。石英二长闪长岩 LA ICP MS 锆石 U Pb 年龄为（122．0±1．8）Ma，代表岩浆的结晶年龄。石英二长闪长岩具低硅（57．26％～58．88％）、高铝（16．58％～17．50％）、富镁（2．65％～2．98％）特征，铝饱和指数（A/CNK）为0．93～1．09，富集轻稀土元素（LREE/HREE＝6．28～7．25），δEu 为0．85～1．05，富集大离子亲石元素 Rb、U、La、Sr、Sm，亏损高场强元素 Nb、Ta、Zr、Hf 等，相对于原始地幔具高 Sr[（87 Sr/86 Sr）i ＝0．705023～0．705453]、低Nd[εNd （t）＝-0．18～2．43]的同位素组成和古老的 Nd 同位素二阶段模式年龄（T DM2＝0．78～1．03 Ga），属于偏铝质过铝质岛弧型花岗岩。多龙矿集区色那金矿早白垩世末岩浆活动与成矿作用很可能是班公湖怒江洋向北俯冲诱发洋壳物质部分熔融，并有少量俯冲沉积物（3．1％～5．1％）和幔源岩浆参与部分熔融混合形成母岩浆，再经一定程度的分异结晶作用和接触交代作用而形成。
색나금광시서장다룡광집구내발현적일개천성저온열액형금광점，기성암성광시대일직결핍정학적년대학약속。대해금광석영이장섬장암진행료 LA ICP MS 고석 U Pb 정년、주미량원소분석화Sr Nd 동위소조성연구，수차획득료다룡광집구색나금광부광암석적성암시대。석영이장섬장암 LA ICP MS 고석 U Pb 년령위（122．0±1．8）Ma，대표암장적결정년령。석영이장섬장암구저규（57．26％～58．88％）、고려（16．58％～17．50％）、부미（2．65％～2．98％）특정，려포화지수（A/CNK）위0．93～1．09，부집경희토원소（LREE/HREE＝6．28～7．25），δEu 위0．85～1．05，부집대리자친석원소 Rb、U、La、Sr、Sm，우손고장강원소 Nb、Ta、Zr、Hf 등，상대우원시지만구고 Sr[（87 Sr/86 Sr）i ＝0．705023～0．705453]、저Nd[εNd （t）＝-0．18～2．43]적동위소조성화고로적 Nd 동위소이계단모식년령（T DM2＝0．78～1．03 Ga），속우편려질과려질도호형화강암。다룡광집구색나금광조백성세말암장활동여성광작용흔가능시반공호노강양향북부충유발양각물질부분용융，병유소량부충침적물（3．1％～5．1％）화만원암장삼여부분용융혼합형성모암장，재경일정정도적분이결정작용화접촉교대작용이형성。
The Sena gold deposit recently discovered in Duolong metallogenic concentrated area is an epithermal gold deposit.There is few high-precision petrogenic and metallogenic geochronological data. The zircon U Pb dating,the major elements,trace elements and zircon Sr Nd isotopic data of the ore-hosting quartz monzobiorite in Sena deposit are reported in this paper.Weighted mean U Pb age of the Zircon from the quartz monzobiorite,(122.0 ± 1.8)Ma,can be regarded as the age of magmatic crystallization.The ore-hosting quartz monzobiorite in the Sena gold deposit is characterized by low SiO2 (57.26% to 58.88% ),high Al2 O3 (16.58% to 17.50%),high MgO (2.65% to 2.98%),(A/CNK)=0.93 to 1.09,rich in LREE (LREE/HREE=6.28 to 7.25),Eu=0.85 to 1.05,meanwhile by high Rb, U,La,Sr,Sm contents,coupled with low Nb,Ta,Zr,Hf contents.Compared with primary mantle, the quartz monzobiorite in Sena gold deposit has respectively high Sr [( 87 Sr/86 Sr)i = 0.705 023 to 0.705 453],low Nd[εNd (t)=-0.18 to 2.43].The model age (T DM2 =0.78 to 1.03 Ga)indicates that the quartz monzobiorite belongs to the over aluminum granite. Authors suggest that the Early Cretaceous magmatism and mineralization be caused by crystallization differentiation and contact metasomatism of parent magma which consist of partial melting materials,few sediments and mantle derived magma.