Earth’s silica-rich continental crust is unique among the terrestrial planets and is critical for planetary habitability. Cratons represent the most imperishable continental fragments and form about 50% of the continental crust of the Earth, yet the mechanisms responsible for craton stabilization remain enigmatic¹. Large tracts of strongly differentiated crust formed between 3 and 2.5 billion years ago, during the late Mesoarchaean and Neoarchaean time periods². This crust contains abundant granitoid rocks with elevated concentrations of U, Th and K; the formation of these igneous rocks represents the final stage of stabilization of the continental crust^2,3. Here, we show that subaerial weathering, triggered by the emergence of continental landmasses above sea level, facilitated intracrustal melting and the generation of peraluminous granitoid magmas. This resulted in reorganization of the compositional architecture of continental crust in the Neoarchaean period. Subaerial weathering concentrated heat-producing elements into terrigenous sediments that were incorporated into the deep crust, where they drove crustal melting and the chemical stratification required to stabilize the cratonic lithosphere. The chain of causality between subaerial weathering and the final differentiation of Earth’s crust implies that craton stabilization was an inevitable consequence of continental emergence. Generation of sedimentary rocks enriched in heat-producing elements, at a time in the history of the Earth when the rate of radiogenic heat production was on average twice the present-day rate, resolves a long-standing question of why many cratons were stabilized in the Neoarchaean period.

地球富含二氧化硅的大陆地壳在类地行星中是独一无二的，对于行星的宜居性至关重要。克拉通是最不朽的大陆碎片，约占地球大陆地壳的 50%，但克拉通稳定的机制仍然是个谜¹。大片强烈分异的地壳形成于 3 至 25 亿年前，即中太古代晚期和新太古代时期²。该地壳含有丰富的花岗岩类岩石，且 U、Th 和 K 浓度较高；这些火成岩的形成代表着大陆地壳稳定的最后阶段^2,3。在这里，我们表明，由海平面以上大陆块的出现引发的地下风化促进了地壳内熔融和过铝质花岗岩岩浆的生成。这导致了新太古宙时期大陆地壳的成分结构的重组。陆地风化作用将产热元素集中到陆源沉积物中，这些沉积物融入了地壳深处，推动了地壳融化和稳定克拉通岩石圈所需的化学分层。陆上风化与地壳最终分异之间的因果链表明，克拉通稳定是大陆出现的不可避免的结果。在地球历史上，放射性热产生速率平均是当今速率的两倍时，富含产热元素的沉积岩的产生解决了一个长期存在的问题：为什么许多克拉通在新太古代时期。