Eclogite masses and some other rocks in Donghai-Ganyu area of JiangsuProvince show many chairactoristics of ophiolites and seem to be relict fra-gments of the oceanic crust.The protoliths must be basic lava and cumulatemafic rocks of ophiolftes,The basalt exhibits chemical composition of oceanicridge tholeiite and contains abundant large-ion lithophile elements,REE andLREE,thus belonging to E-MoRB,These rocks were formed in an ocearnicbasin environment between the Subei-Jiaonan terrane and the Jiaobei terra-ne,with their magma derived from the partial melting of the enriched ma-ntle and the deep mantle current.As a result of plate subduction and colli-sion,these plutonic eclogites were emplaced in different horizons of the Do-nghai Group.