中亚造山带中元古代微陆块构造归属及其对中元古代地球系统演化的启示

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中图分类号：P548 DOI：10.16152/j. cnki. xdxbzr.2025 -03-002

Abstract Contrasting the dramatic changes in the preceding and succeeding eras，the Mesoproterozoic era （ 1.6～1.0Ga ）witnessed environmental and evolutionary stasis. However，during Mesoproterozoic time，accretionary orogeny was intensely operative in the periphery of the Nuna supercontinent after its amalgamation， follwed by the extension and breakup of Nuna，and paved the way to the formation of the Rodinia supercontinent.Several Mesoproterozoic microcontinents have been identified along the southern margin of the Central Asian orogenic belt（CAOB）and consist of 1.56～1.36 Ga crystalline basements and greenschist- to amphibolite-facies metamorphosed volcanic-sedimentary rocks，whose tectonic afinity remains controversial.Based on an integrated comparison of basement composition，nature of magmatic activity，and detrital zircon U-Pb ages and Hf isotopes，a western Amazonian affinity in the Nuna’s periphery was established for the Mesoproterozoic microcontinents in the southern CAOB.Reconsidering the multiple proxies of the Earth's surface and deep systems in the Mesoproterozoic，we emphasize the energetic Mesoproterozoic era，during which the intense accretionary orogeny along the Nuna's periphery might have stimulated environmental oxygenation and eukaryotic inovation in the Mesoproterozoic.The spatiotemporal correlations between the deep Earth processes and surficial environmental and biotic evolution，along with their primary mechanism，represent critical scientific issues that warrant further in-depth investigation.

Keywordstectonic afinity；Central Asian orogenic belt；Mesoproterozoic ；Nuna supercontinent； subduc-tion-accretion

元古宙是宜居地球形成和演化的关键时期，在古元古代早期和新元古代晚期地球表生环境生命系统发生了重大变革，最具代表性的是雪球地球极端气候和重大增氧事件[1-5]。（剩余24470字）