试论大火成岩省与成矿作用  

A Preliminary Discussion on Large Igneous Provinces and Associated Ore Deposits

作　　者：肖龙[1] Franco Pirajno 何琦[1] 

机构地区：[1]中国地质大学地球科学学院,武汉430074 [2]Geological Survey of Western Australia 100 Plain Street,East Perth,WA 6004,Australia

出　　处：《高校地质学报》2007年第2期148-160,共13页Geological Journal of China Universities

基　　金：国家自然科学基金(40572031)资助成果

摘　　要：根据组成大火成岩省的岩浆类型不同,大火成岩省可以分为两类,一是以基性火成岩为主的镁铁质大火成岩省(MLIPs),二是以酸性火成岩为主的长英质大火成岩省(SLIPs)。它们都是由于在异常高的地幔热流参与下导致地幔或地壳大规模熔融形成的。大火成岩省独特的巨量岩浆活动是引起多层次物质和能量交换的重要场所。成矿物质的聚集导致成矿作用和矿床的形成是必然的,因此大火成岩省本身就是一个大成矿系统。在这个成矿系统中,由于物源、成分、温度、压力、流体和氧逸度等条件的差异性,形成不同种类的矿化和矿床,并构成一定的成矿系列。镁铁质大火成岩省中形成的矿床类型有岩浆硫化物型Cr-Cu-Ni-PGE矿床和Ti-Fe氧化物型V-Ti-Fe矿床,热液型的Cu-Pb-Zn-Au-Ag矿床,以及远程低温热液矿床等。长英质大火成岩省形成的矿床类型为岩浆和交代型、热液型Cu-Pb-Zn-Au-Ag,W-Sn,U-Th-REE矿床,以及Sb-As矿床等。加强对大火成岩省及其成矿机理的研究,有望形成新的成矿理论和加速超大型矿床的发现。Large igneous provinces （LIPs） are grouped into mafic （MLIPs） and silicic （SLIPs）, based on their dominant components, marie or silicic volcanic and intrusive rocks, respectively. The formation of these LIPs requires extremely high heat flow from mantle, which results in extensive melting of mantle, subcontinental lithospheric mantle and lower crust. The typically massive magmatism of LIPs also results in extensive energy and materials exchange thereby causing the formation of a range of important ore systems. MLIPs and SLIPs have different magma sources, compositions, temperatures, pressures, fluids and oxygen fugacities, and experience distinct magmatic evolutionary histories. MLIPs tend to form magmatic Cr-Cu-Ni-PGE sulfide and V-Ti-Fe oxide deposits, some hydrothermal Cu- Pb-Zn-Au-Ag deposits and distal epithermal systems. SLIPs, on the other hand, tend to form metasomatic and/or hydrothermal Cu-Pb-Zn-Au-Ag, W-Sn, U-Th-REE, As-Sb and low-sulfidation epithermal ore systems. Detailed studies of LIPs and associated ore deposits will enable better constrain the metallogenic and ore genesis models, which in turn will help in the discovery of giant ore deposits.

关 键 词：大火成岩省 镁铁质大火成岩省 长英质大火成岩省 成矿作用 地幔柱 

分 类 号：P588.1[天文地球—岩石学] P611[天文地球—地质学]