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最近发表的关于地壳演化的模式出现了一些极端矛盾的观点。一种观点认为大陆壳完全发育在40亿年以前,在整个地质时期,地幔只有数量上的重复循环,而没有地壳质量的基本变化(即大陆稳定论);另一种与此相反的观点,认为早期的大陆壳(37亿年)呈小而限于局部的小碎块产出,而一度为年轻的大陆壳是克拉通化的,不能大量地返回地幔中。这种观点相当于地幔不可逆的化学分异概念,在地质时期伴随有大陆壳的生长(即大陆生长说)。介于上述两种矛盾观点之间,还有人认为,一些相对小的大陆组分,可以有选择地重复循环到地幔中去。这不包括大规模的大陆壳重复循环,而只有大
There have been some extreme contradictions in the recently published model of the evolution of the crust. One view is that the continental crust was fully developed more than 4 billion years ago and that there was only a quantitative cyclic repetition of the mantle throughout the geological period without a fundamental change in the quality of the crust (ie, the continental stability theory). On the other hand, The early continental crust (3.7 billion years) was thought to be small but limited to small, locally produced fragments, whereas the once-younger continental crust was cratonized and could not return massively to the mantle. This view is equivalent to the concept of irreversible chemical differentiation of the mantle, accompanied by the growth of the continental crust during the geological period (ie, the growth of the mainland). Between the above two contradictory points of view, some people think that some relatively small continental components can be selectively recycled to the mantle. This does not include large continents repeating the cycle, but only large