作　　者： ; ;

机构地区： 中国科学院广州地球化学研究所

出　　处： 《南极研究》 1995年第1期17-24,共8页

摘　　要： 报道了５２个南极铁陨石的１３个元素的浓度，并根据其构造和Ｇａ，Ｇｅ，Ｎｉ，Ｉｒ及其它微量元素的含量进行了分类，５２个铁陨石由１６个ＩＡＢ，１２个ＩＡＢ，１个ＩＥ，３个ＩＩＡＢ，１个ＩＩＣＤ，１个ＩＶＡ及１８个未分群的化学群组成。ＩＡＢ，ＩＩＣＤ及ＩＥ为非岩浆成因的铁陨石群，它们是由球粒陨石质母体近表面区冲击产生单独的熔体池形成的，ＩＡＢ，ＩＩＡＢ及ＩＶＡ显示金属岩浆分离结晶作用的特征，为岩浆成因的铁陨石。岩浆群铁陨石元素－Ｎｉ的斜率一般比非岩浆群高。有意思的是在南极回收的５２个铁陨石中，相对于非南极铁陨石ＩＡＢ和未分群的铁陨石丰度较高（分别为２７．８％和４７．２％），而ＩＩＡＢ群的丰度较低（５．８％），它们含有以前未采到样品的母体形成区域、质量、冲击碰撞频率的信息。 We report concentrations of 13 elements in the metal of 52 Antarctic iron meteorites and their classification based on the structures and their Ga,Ge,Ni,Ir and other trace elemental contents.The 52 iron meteorites assigned to chemical group consist of 16 of IAB,12 of IIAB,1 of IIE,3 of IIIAB,1 of IIICD,1 of IVA and 18 of ungrouped irons.The IAB,IIICD and IIE iron meteorite groups are considered to be of nonmagmatic origin.Nonmagmatic IAB,IIICD and IIE irons formed as individural pools of a chondritic body.The other groups,IIAB,IIIAB and IVA show evidence of having originated by fractional crystallization of a metallic magma.The slopes on element Ni trends are generally higher in magmatic than in the nonmagmatic groups.Most interestings are that there are high abundance of ungrouped and IAB (47.2% and 27.8%,respectively) and low abundance of IIIAB (5.8%) iron meteorites from Antarctica relative to non Antarctic iron meteorites,which contain information about previously unsampled parent planets,mass,shock and collision,as well as nebula regions.

关 键 词： 南极 南极陨石 铁陨石 化学成分 分类

领　　域： [天文地球]