摘要
///The Qingshixia zone of Qincheng-Hami rock group is metamorphic basalt, actinolite schist, metamorphic tuff, metamorphic acid tuff, metamorphic volcanic tuff, metamorphic lithic sandstone, phyllite etc.. Volcanic rock group is basalt-rhyolite group, little andesites, has bimodal volcanic character, belong to rift volcanic group. The chemical character of volcanic rock is alkali-basalt course, natrium type REE distribution pattern rich in light REE(LREE); δEu=0.88-0.98, is Eu smoothness type, have marble magma character. Trace element has the character of basalt in continental plate and tally with rift valley’s character. The environment of structure shows the character of basalt sufficiently, have the character of evolvement from altiplano effusive rock to rift valley. The year of isotops Sm-Nd is 707~757 Ma, is early Nanhuan. Nanhuan is globality parting ear, this volcanic rock’s character is parting type rift valley volcanic rock, so this stratum belong to Nanhuan, can contrast to Beiyixi Group of Kuluke Tage area and New Set up to Qingshixia Formation.