Intra-oceanic arc accretion along Northeast Asia during Early Cretaceous provides a plate tectonic context for North China craton destruction

Abstract

North China craton destruction (i.e., NCC destruction) during the Early Cretaceous is typically considered within the context of continuous, westward subduction of the Izanagi /paleo-Pacific plate beneath eastern Eurasia (i.e., Andean-style subduction). However, geological evidence indicates intra-oceanic arc accretions along east Eurasia during the Early Cretaceous that are incompatible with Andean-style plate tectonics. Here we review oceanic terrane accretions along NE Asia during Cretaceous times from published magmatism, stratigraphy, and paleomagnetism. We synthesize an alternative ‘intra-oceanic subduction’-style NE Asian plate tectonic model between ~15–40° N latitudes during the Early Cretaceous (130–100 Ma) and discuss implications for NCC destruction. Well-known NE Asian magmatism migrated >1000 km inboard to NE China during the Jurassic, and then >1000 km outboard during early Cretaceous (140–110 Ma). Early Cretaceous NE Asian igneous rocks include: (1) arc-related igneous rocks, (2) 132–99 Ma adakites in Japan and Sikhote-Alin, and (3) 145–120 Ma K-rich adakites in NE China. Roughly co-eval to these periods (130 to 100 Ma), intra-oceanic arcs accreted diachronously along the Sambagawa belts, SW Japan, Oku-Niikappu belts, NE Japan, and Kema and Kiselevka-Manoma, Russian Far East. Based on the adakite geochemistry and spatiotemporal overlap between the arc accretions and adakites, we link the NE China adakites to lower NCC crustal melting, whereas the Japan-Sikhote Alin adakites originated from oceanic slab melting. We show that eastern Eurasia-NW Panthalassan plate tectonics during the Early Cretaceous was more complex than generally recognized, involving intra-oceanic subduction zones and multiple oceanic plates. The Early Cretaceous-aged NE Asian adakites were generated within elevated mantle geotherms during 140–110 Ma slab rollback and 130–100 Ma intra-oceanic arc accretions. Oceanic mantle emplaced during these events replaced the NCC subcontinental lithospheric mantle with more juvenile mantle during final NCC destruction at 115 Ma. The more complete plate tectonic picture provided here suggests that NCC destruction models that rely on straightforward Andean-style subduction are likely oversimplified. Instead, future NCC destruction studies should include more complex geodynamics with intra-oceanic subduction and additional plates that will alter boundary conditions for geodynamic modeling, petrogenesis, and magmatic mixing models.

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