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江苏六合一带碱性玄武岩中出露有以尖晶石二辉橄榄岩为主的地幔捕虏体。这些地幔矿物中普遍有硫化物相出现 :(1)被寄主矿物捕获的早期硫化物颗粒 ;(2 )产于矿物晶粒边界或次生裂隙中的裂隙充填物 ;(3)硫化物包裹体 ,包括单相硫化物包裹体、硫化物 -玻璃两相熔体包裹体和 CO2 -硫化物 -玻璃 (含硅酸盐子矿物 )的多相包裹体。电子探针分析表明 ,硫化物包裹体比裂隙中硫化物具有更高的相对 Fe和 S含量 ,较低的 Ni含量。硫化物包裹体的 Ni/ Fe(mol比值 )为 0 .14~ 1.73,一般为 0 .70~ 1.5 5 ,而裂隙中硫化物的 Ni/ Fe为 1.76~ 7.0 3。汉诺坝、新昌和麒麟等地与六合相同 ,相对裂隙中硫化物来讲硫化物包裹体更富 Fe和 S,而贫 Ni。同种类型硫化物对比发现 ,从六合、新昌、汉诺坝至麒麟有 S相对增加的趋势 ,Fe也依六合、新昌、麒麟至汉诺坝顺序增加 ;而 Ni(+Co)则按六合、新昌、麒麟至汉诺坝顺序减少。这说明同一地区地幔岩中裂隙硫化物和硫化物包裹体的成分存在某种继承关系 ,其硫化物成分与该地区地幔橄榄岩的来源深度 (或经历部分熔融时的深度 )有一定联系
Basaltic rocks in the Liuhe area of Jiangsu Province are characterized by mantle xenoliths dominated by spinel lherzolites. Sulfide phases commonly occur in these mantle minerals: (1) early sulphide particles captured by host minerals; (2) crevice packings that occur at grain boundary or secondary fissures; (3) sulfide inclusions , Including single-phase sulfide inclusions, sulfide-glass two-phase melt inclusions and CO2-sulfide-glass (silicate-containing minerals) multiphase inclusions. Electron probe analysis shows that sulfide inclusions have higher relative Fe and S contents and lower Ni contents than sulphides in the cracks. The Ni / Fe (mol ratio) of sulfide inclusions ranges from 0.14 to 1.73, usually from 0.70 to 1.55, while the Ni / Fe of sulphides in fractures is from 1.76 to 7.03. Hannuoba, Xinchang and unicorn are all the same as Luhe, but the sulphide inclusions are richer in Fe and S than lean sulphide in relative fissures, and lean in Ni. Compared with the same type of sulfides, there is a relative increase trend of S from Luhe, Xinchang, Hannuoba to Kirin, and the order of Fe also increases according to Luhe, Xinchang and Kirin to Hannuoba; and Ni (+ Co) Xinchang, Kirin to Hannock dam order reduction. This indicates that there is some inheritance relationship between the composition of sulfide ores and sulfide inclusions in the mantle rocks in the same area and that the sulfide composition is related to the source depth of the mantle peridotite (or the depth of partial melting)