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达拉布特蛇绿岩带的镁铁质岩属亚碱性和碱性系列，可能是弧后盆地火山活动的产物。根据镁铁质岩的层位关系、岩浆来源和微量元素特征，可将该盆地的地质演化概括为扩张阶段和封闭阶段。盆地扩张阶段早、中期喷发的镁铁质岩具有低的稀土和不相容元素丰度，而在盆地封闭阶段晚期喷发的碱性玄武岩，其特点是稀土和大多数不相容元素丰度极大增高，其稀土元素分布模式为轻稀土元素强烈富集型。
The mafic rocks in the Dalbott ophiolite zone are subbasin and alkaline in nature and may be the product of volcanic activity in the back-arc basin. According to the stratigraphic relationship of mafic rocks, magma source and trace elements, the geological evolution of the basin can be summarized as the expansion phase and the closure phase. The mafic rocks erupted in the early and mid-stage of the basin expansion have low abundances of rare earths and incompatible elements, whereas the alkaline basalts erupted in the late stage of basin closure characterized by rare earths and most incompatible elements Greatly increased, the rare earth element distribution pattern is strongly enriched in light rare earth elements.