The ophiolite age is about 440Ma and the metamorphic age of the first stage (amphibolite facies or granulite facies) is about 364Ma obtained with the method of concordia diagram.

• 所获锆石系单一来源的火山碎屑，故采用分组多颗粒锆石U-Pb同位素定年法，并依谐和图法，获得（440±18）Ma榆树沟蛇绿岩的形成年龄和（364±5）Ma的第一期（角闪岩相或麻粒岩相）变质年龄。