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Title: Phanerozoic cratonization by plume welding
Deformation-resistant cratons comprise >60% of the continental landmass on Earth. Because they were formed mostly in the Archean to Mesoproterozoic, it remains unclear if cratonization was a process unique to early Earth. We address this question by presenting an integrated geological-geophysical data set from the Tarim region of central Asia. This data set shows that the Tarim region was a deformable domain from the Proterozoic to early Paleozoic, but deformation ceased after the emplacement of a Permian plume despite the fact that deformation continued to the north and south due to the closure of the Paleo-Asian and Tethyan Oceans. We interpret this spatiotemporal correlation to indicate plume-driven welding of the earlier deformable continents and the formation of Tarim’s stable cratonic lithosphere. Our work highlights the Phanerozoic plume-driven cratonization process and implies that mantle plumes may have significantly contributed to the development of cratons on early Earth.  more » « less
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National Science Foundation
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