Some geologists，however，on the basis of observations concerning mantle xenoliths， argue that the mantle is not layered，but that heterogeneity is created by fluids rich in "incompatible elements" (elements tending toward liquid rather than solid state)percolating upward and transforming portions of the upper mantle irregularly，according to the vagaries of the fluids' pathways.
但是，某些地質(zhì)學(xué)家，以對地幔捕虜巖體(xenolith)所作的觀察為依據(jù)，指出地幔并非是分層排列的，相反，地幔的異質(zhì)性是由那些富含"不相容成分"的流質(zhì)構(gòu)成的，這些成分趨向于流體而非固體的狀態(tài)，自下而上滲透擴(kuò)散，并依照這些流質(zhì)流向的任意性，不規(guī)則地將上部地幔的某些部分予以改變。