Mantle Basis Observations Heterogeneity Created Fluids Argue Incompatible

意群训练： Some geologists , however , on the basis o f 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 upwar d and transforming portions of th e upper mantle irregularly , according t o the vagaries of the fluids' pathways .

标志： 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/］/.

译文： 但是 ，一些地质学家 （基于关于地幔捕虏岩的观察 ）认为 ，地幔 不是分层的 ，而 其不同的成分 是/由一些流体造成的 ，这些流体［富含“不相容成分”（即那些趋向于作为液体而非固体而存在的成分），（这些物质 向上渗透，并/依照这些流体所经过的随机路径/不规则地改变了上地幔的某些部分）］/。

解释： 本句的主句中有一个长插入语however, on the basis of observations concerning mantle xenoliths ，割裂了主谓。但句子的主要难度还是在that引导的宾语从句中。从句中有由but 所连接的两个句子，第二个句子that heterogeneity is created /by fluids 之后出现了大段的对fluids的修饰成分，一直延续到句末。首先是rich in “incompatible elements”修饰fluids；后面又有一个同位语和一个分词结构，都是修饰“incompatible elements”的；最后还有一个状语来修饰那个分词结构，层层修饰，比较复杂。