中国与基性—超基性岩有关的Cu－Ni（Pt）矿床成矿系列类型

中国与基性—超基性岩有关的Ｃｕ－Ｎｉ（Ｐｔ）矿床，主要形成于以前寒武系为基底的大陆裂谷，部分形成于增生褶皱带中显生宙地层为基底的裂陷槽环境。根据形成时代、当时所在的构造环境单元及成矿岩浆系列，划分为９个矿床成矿系列和８个矿床成矿亚系列。成矿时代以元古代、晚古生代为主。现今，矿床主要分布于地台边缘，造山带中也有产出，但不代表其当时形成的地质背景。成矿物质来源为上地幔，原始岩浆以上地幔部分熔融的高ＭｇＯ拉斑玄武岩（拉斑橄榄玄武岩）岩浆系列为特征，也有钙碱性岩浆（喀拉通克）和科马提岩岩浆系列（桂北）。地壳物质混染比较普遍。矿床成因类型主要为岩浆熔离型，且以硅酸盐岩浆上侵前的深部熔离作用为主。还有热液成因类型（煎茶岭）。矿床成矿系列的时空分布与中国大陆的构造演化密切相关

METALLOGENIC SERIES TYPES OF Cu Ni(Pt) DEPOSITS RELATED TO BASIC-ULTRABASIC ROCKS IN CHINA

The Cu Ni (Pt) mineral deposits related to basic-ultrabasic rocks in China occurred mainly in continental rift that basement is Precambrian system and some occurred environment in accretional folded belt and the aulacogen basement is Phanerozoic eon strata. On the basis of metallogenic epoches,tectonic setting units of mineralization process and metallogenic specialization of magma series,these deposits in China could be divided into nine metallogenic series and eight metallogenic subseries. Metallogenetic epoches are Proterozoic and late Palaeozoic era mainly,and today,these mine ral deposits in China distributed at margin of platforms and some in orogenic belts,but it does not really show their mineralizing geological setting.Ore forming material came from upper mantle and original magma was tholeiitic magma series (tholeiitic dorgalite)which was partial melting of upper mantle and high content of MgO.There are metallogenetic types of calc alkalic magma series(Karatongke)and komatiitic magma series (northern Guangxi).Original magma series hybridized with crustal material commonly.Types of deposit genesis are mainly magmatic liquation,but plutonic liquation is dominance before uptrusion of silicate magma,and hydrothermal deposits are occurred,for example Jianchaling deposit.Space time distribution of metallogenic series depended on geotectonic evolution of Chinese continent closely.