电气石——成岩成矿作用的灵敏示踪剂  

Tourmaline——A Sensitive Tracer for Petrogenesis and Minerogenesis

作　　者：蒋少涌[1] 于际民[1] 倪培[1] 凌洪飞[1] 

机构地区：[1]南京大学地球科学系成矿作用国家重点实验室,210093

出　　处：《地质论评》2000年第6期594-604,共11页Geological Review

基　　金：国家杰出青年科学基金 (编号49925306);国家重点基础研究项目 (编号G1999043208)

摘　　要：本文详细论述了电气石的化学组成(主化学元素、微量元素和稀土元素)和同位素组成(H、O、B、Si、Rb/Sr、Sm/Nd、Pb/Pb和K/Ar)特征,提出电气石可以作为研究成岩成矿作用的一个灵敏示踪剂。利用电气石的主化学元素和微量、稀土元素组成,可以有效指示其形成的物理化学环境,还可以作为一种有用的找矿标志,指示矿化的存在,并可能用于区分矿化类型和矿体规模。电气石的稳定同位素和放射性同位素研究,已经用于示踪成岩成矿物质来源,推断源区特征和流体性质,指示岩石和矿床成因。同时,还有可能提供电气石形成及成岩成矿作用年龄信息。lourmaime is a complex borosihcate mineral which occurs in many granites, pegmatites, metamorphic and sedimentary rocks and in a variety of hydrothermal ore deposits, especially some massive sulfide deposits, mesothermal Au-Ag and Sn-W deposits. There is a wide variation in chemical compositions of tourmaline from various geological settings, which typically reflect the environments in which tourmaline is crystallized. A large range of trace elements including Cu, Pb, Zn, Ag, Sn, Cr, V, Sr and REE are documented in tourmaline as minor or trace constituents. Their concentration levels and distribution patterns record their paragenetic conditions and are good indicators for petrogenesis, minerogenesis, and miheral prospecting. Stable isotopes of O, H, B and Si in tourmaline are suggested to be good tracers for hydrothermal fluids, fluid -rock interaction and the origin of rocks and ore deposits, and can provide valuable information regarding temperatures of tourmaline formation. The Rb-Sr and Sm-Nd isotopic compositions of tourmaline have major implications for source reservoirs and the nature of hydrothermal fluids, and can yield geological meaningful ages for tourmaline formation and related mineralization. Pb-Pb isotope studies of tourmaline obtained by stepwise Pb leaching techniques have been proven to be a good geochronometer, and K-Ar, 40Ar-39Ar systematics of tourmaline may also be useful for age determinations. Therefore, tourmaline has been used as a sensitive tracer for rock-forming and ore-forming processes, and for tourmalinization dating and associated hydrothermal alteration , mineralization, and metamorphism.

关 键 词：电气石 化学组成 示踪剂 成矿作用 成岩作用 

分 类 号：P578[天文地球—矿物学]