变质矿床成因分类的讨论

Discussion on Genetic Classification of Metamorphic Ore Deposits

在探讨了变质矿床的定义并结合前人研究的基础上,对变质矿床初步提出了一个新的成因分类方案。该方案共分为五个大类和十三个亚类,并对每个大类和亚类都提出了一些代表性矿床实例。新的变质矿床成因分类方案为:(1)受变质矿床类,分为受变质硅铁质建造沉积矿床、受变质硅铁质建造火山–沉积矿床、受变质其它建造沉积–火山沉积矿床、受变质火成岩改造矿床和受变质细碧角斑质火山喷发沉积矿床五个亚类;(2)区域变质作用变成矿床类,分为变质重结晶型、变质化学反应重组型和变质热液型三个亚类;(3)局部变质作用变成矿床类,分为接触交代夕卡岩矿床、局部接触热变质变成矿床和局部动力变质变成矿床三个亚类;(4)受变质沉积–火山沉积变质热液叠加改造矿床类;(5)混合岩化作用形成矿床类,又分为混合岩化交代型和后期混合岩化热液型两个亚类。

This paper discusses the definition of the metamorphic ore deposits. On the basis of the preceding study, a new genetic classification scheme is tentatively put forward, in which 5 types and 13 subtypes are discriminated, and representative ore deposits examples are given for each type and subtype. The new classification is shown as follows. （1） Metamorphosed ore deposits, which are subdivided into five subtypes： the metamorphosed banded iron formation （BIF） sedimentary subtype, the metamorphosed BIF volcano-sedimentary subtype, the other metamorphosed sedimentary-volcano-sedimentary formation subtype, the metamorphosed igneous alteration ore deposits subtype and the metamorphosed spilite-keratophyric volcano-eruptive sedimentary ore deposits subtype; （2） Metamorphic ore deposits of regional metamorphism. Three subtypes are included： the metamorphic recrystallization subtype, the components recombination by metamorphic chemical reactions subtype and the metamorphic hydrothermal ore deposits subtype; （3） Metamorphic ore deposits of local metamorphism. Three subtypes are determined： the skarn ore deposits of contact- metasomatism subtype, the local thermal contact-metamorphic subtype and the local dynamo-metamorphic subtype; （4） Metamorphosed sedimentary-volcano-sedimentary ore deposits superimposed and transformed by metamorphic hydrothermal solutions; （5） Ore deposits by migmatism. Two subtypes are included： the migmatitic-metasomatic subtype and the later stage migmatitic-hydrothermal subtype.