Isotopic characteristics and petrogenesis of the lamproites and kimberlites of central west Greenland
Isotopic characteristics and petrogenesis of the lamproites and kimberlites of central west Greenland
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DOI：
10.1016/0024-4937(89)90029-7
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发表时间：
1989-04
期刊：
影响因子：
3.5
通讯作者：
D. Nelson
中科院分区：
文献类型：
--
作者：
D. Nelson
金伯利岩侵入西西米尤特（原Holsteinsborg）地区的中西部格陵兰岛在早古生代有初始87 Sr 86 Sr之间的0.7028和0.7033和Nd之间的+1.3和+3.9。同一地区的中元古代钾质钾煌斑岩的初始87 Sr 86 Sr在0.7045和0.7060之间，Nd在− 13和− 10之间，初始Pb同位素组成为非放射成因。同位素数据支持金伯利岩岩浆的软流圈地幔源，与其他地方的"玄武岩"金伯利岩一样，而钾镁煌斑岩岩浆源与对流地幔隔离演化> 1000 Ma，可能在格陵兰克拉通的次大陆岩石圈地幔内，在钾镁煌斑岩就位之前。
Kimberlites which intruded the Sisimiut (formerly Holsteinsborg) region of central west Greenland during the Early Palaeozoic have initial 87 Sr 86 Sr between 0.7028 and 0.7033 and ϵ Nd between+ 1.3 and+ 3.9. Mid-Proterozoic potassic lamproites from the same region have initial 87 Sr 86 Sr between 0.7045 and 0.7060, ϵ Nd between− 13 and− 10 and unradiogenic initial Pb isotopic compositions. The isotopic data favour an asthenospheric mantle source for the kimberlite magmas, in common with “basaltic” kimberlites from other localities, whereas the lamproite magma sources evolved in isolation from the convecting mantle for> 1000 Ma, probably within the subcontinental lithospheric mantle of the Greenland craton, prior to emplacement of the lamproites.