东秦岭松树沟蛇绿岩Sm-Nd同位素年龄的地质意义

Sm Nd ISOTOPIC AGES OF THE SONGSHUGOU OPHIOLITE FROM THE EAST QINLING AND ITS GEOLOGICAL SIGNIFICANCE

摘要: 东秦岭松树沟蛇绿岩主要由变质橄榄岩和变质玄武岩组成。变玄武岩全岩ＳｍＮｄ同位素等时年龄为（１０３０±４６（２δ））Ｍａ，ＩＮｄ＝０．５１１６１±５（２δ），εＮｄ（ｔ）＝＋５．７±０．２，代表蛇绿岩中玄武岩的形成年龄。这一年龄的确定，为探讨秦岭区中晚元古代的古构造格局提供了重要的证据

Abstract: The Songshugou ophiolite consists mainly of meta perdotite and meta basalt. Five whole rock samples of meta basalt give a Sm Nd isochron age of （1030±46 ） Ma with I Nd =0.51161±5 （2δ） and ε Nd （t） = +5.7±0.2, which may represent the formation age of the basalt. This age gives some important information about the Middle Late Proterozoic tectonic framework in the Qinling region.