科技通报
科技通報
과기통보
Bulletin of Science and Technology
2015年
11期
35-41
,共7页
贾宝剑%钱俊锋%陈志国%金宠%严育通%王海宝
賈寶劍%錢俊鋒%陳誌國%金寵%嚴育通%王海寶
가보검%전준봉%진지국%금총%엄육통%왕해보
硫铅同位素%成矿物质来源%铜钨多金属矿%潘家%钦杭成矿带
硫鉛同位素%成礦物質來源%銅鎢多金屬礦%潘傢%欽杭成礦帶
류연동위소%성광물질래원%동오다금속광%반가%흠항성광대
sulfur and lead isotopes%sources of ore-forming materials%Panjia%Qinzhou-Hangzhou metallo genic belt
浙江淳安潘家铜钨多金属矿是浙西新近发现的大-中型地层-构造-岩浆综合控制型矿床,矿体主要产于大铜坑岩体与震旦系蓝田组中及其接触带。本文尝试运用黄铁矿S、Pb同位素示踪的方法探讨矿床成矿物质来源。矿区黄铁矿硫同位素组成δ34S值集中在3.7%~5.3%,且花岗闪长斑岩-蚀变花岗闪长斑岩-角岩化围岩中δ34S值有逐渐增加,反映了硫质应为侵入岩体与沉积地层两个端元的有效混合,且以岩浆源为主的地幔源区特征;Pb同位素组成为高放射成因的Th-型异常铅,同位素组成μ(238U/204Pb)值特征、Zartman构造模式图、Δγ-Δβ成因分类图解显示,矿区铅具沉积成因和岩浆成因两种形成机制,前者为壳源,后者为幔-壳混源。综合研究显示,蓝田组地层和大铜坑岩体均为成矿母岩,且以后者为主,成矿物质为幔-壳混合源区。
浙江淳安潘傢銅鎢多金屬礦是浙西新近髮現的大-中型地層-構造-巖漿綜閤控製型礦床,礦體主要產于大銅坑巖體與震旦繫藍田組中及其接觸帶。本文嘗試運用黃鐵礦S、Pb同位素示蹤的方法探討礦床成礦物質來源。礦區黃鐵礦硫同位素組成δ34S值集中在3.7%~5.3%,且花崗閃長斑巖-蝕變花崗閃長斑巖-角巖化圍巖中δ34S值有逐漸增加,反映瞭硫質應為侵入巖體與沉積地層兩箇耑元的有效混閤,且以巖漿源為主的地幔源區特徵;Pb同位素組成為高放射成因的Th-型異常鉛,同位素組成μ(238U/204Pb)值特徵、Zartman構造模式圖、Δγ-Δβ成因分類圖解顯示,礦區鉛具沉積成因和巖漿成因兩種形成機製,前者為殼源,後者為幔-殼混源。綜閤研究顯示,藍田組地層和大銅坑巖體均為成礦母巖,且以後者為主,成礦物質為幔-殼混閤源區。
절강순안반가동오다금속광시절서신근발현적대-중형지층-구조-암장종합공제형광상,광체주요산우대동갱암체여진단계람전조중급기접촉대。본문상시운용황철광S、Pb동위소시종적방법탐토광상성광물질래원。광구황철광류동위소조성δ34S치집중재3.7%~5.3%,차화강섬장반암-식변화강섬장반암-각암화위암중δ34S치유축점증가,반영료류질응위침입암체여침적지층량개단원적유효혼합,차이암장원위주적지만원구특정;Pb동위소조성위고방사성인적Th-형이상연,동위소조성μ(238U/204Pb)치특정、Zartman구조모식도、Δγ-Δβ성인분류도해현시,광구연구침적성인화암장성인량충형성궤제,전자위각원,후자위만-각혼원。종합연구현시,람전조지층화대동갱암체균위성광모암,차이후자위주,성광물질위만-각혼합원구。
The Panjia Cu-W polymetallic ore deposit is a newly-discovered, large-middle scale deposit in Chun’an, Zhejiang Province. This deposit is strictly controlled by the regional stratum-tectonic-mag?ma. The ore bodies mainly occur in the Datongkeng intrusion rock, the Upper Sinian Lantian Formation, and their contact zone. This paper attempts to discusse the sources of ore-forming materials by using the methods of sulfur and lead isotopic tracing. Studies have shown that the compositionδ34S in pyrite has a narrow variation range of 3.7~5.3%and gradually increases from granodiorite porphyry, altered granodio?rite porphyry, to hornfelsic stratum. The characteristic of sulfur isotopic composition suggests that the sul?fur of Panjia deposit has mixing direct sources of intrusion rock and stratum sedimentary strata, and the former is dominant with a characteristic of mantle source area. The lead isotopic compositions of the Pan? jia ore deposit are all rich in radiogenic Th-type lead. The characteristics of μ (238U/204Pb), Zartman diagrams andΔγ-Δβdiagram suggest that the lead has two kinds of formation mechanism of sedimenta?tion and magmatism, which respectively form the lead isotopes of crust source and mantle-crust source. The comprehensive studies show that the mineralizing mother rocks of the Panjia Cu-W polymetallic ore deposit are both Lantian Formation and Datongkeng intrusion rock, and the former is dominant. In the whole, the ore-forming materials have the characteristic of mixing source area of mantle and crust.