By mcasuring the Sm-Nd and Rb-Sr isotopiccompositions of harzburgite and gabbro from Shimianophiolite suite, we got the whole rock Sm-Nd isochron age of(938 ± 30) Ma (2σ), and the e Nd of 7.6 ± 0.8 (2σ), w...By mcasuring the Sm-Nd and Rb-Sr isotopiccompositions of harzburgite and gabbro from Shimianophiolite suite, we got the whole rock Sm-Nd isochron age of(938 ± 30) Ma (2σ), and the e Nd of 7.6 ± 0.8 (2σ), which showsthat the ophiolite was formed at the Early Neoproterozoic.The obvious change (0.70209-0.70708) of Isr values of theophiolite is caused by the meteoric hydrothermal alteration.The high εNd values indicate that the primitive magma wasderived from the intense depleted mantle rescrvoir. It is sug-gested that this area was in a back-arc basin environmentduring the Early Neoproterozic.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant No.49972024).
文摘By mcasuring the Sm-Nd and Rb-Sr isotopiccompositions of harzburgite and gabbro from Shimianophiolite suite, we got the whole rock Sm-Nd isochron age of(938 ± 30) Ma (2σ), and the e Nd of 7.6 ± 0.8 (2σ), which showsthat the ophiolite was formed at the Early Neoproterozoic.The obvious change (0.70209-0.70708) of Isr values of theophiolite is caused by the meteoric hydrothermal alteration.The high εNd values indicate that the primitive magma wasderived from the intense depleted mantle rescrvoir. It is sug-gested that this area was in a back-arc basin environmentduring the Early Neoproterozic.
