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要旨:
Abstract Changbaishan volcano (China/North Korea) is one of the most active and hazardous volcanic centers in Northeast Asia. Despite decades of intensive research, the eruption history of this stratovolcano remains poorly constrained. One of the major puzzles is the timing of the eruption that produced the Tianwen Yellow Pumice (TYP) deposit at the caldera rim. Here we identify a new cryptotephra layer in sediment core 13PT-P4 from the East Sea. Grain-specific major, minor, and trace element analyses of glass shards allow a clear correlation of this distal tephra to the proximal TYP deposit of Changbaishan. Age-depth modeling using radiocarbon (14C) dates of sediment bulk organic fractions and other tephrochronological markers from the sediment sequence constraints the age of the cryptotephra and thus the TYP eruption to 29,948?29,625 cal yr BP (95.4% confidence interval). Our findings lead to a revision of the history of Changbaishan explosive activity, and show that the volcano has been particularly active during ca. 51?24 ka BP in the last 100 ka. Using high resolution palaeo-proxy records, we find the TYP tephra almost coeval with regional to hemispheric-scale climatic changes known as Heinrich Event 3 (H3). With its precise age determination and wide geographic dispersion, the tephra offers a key isochron for dating records of past climatic changes and addressing the phasing relationships in environmental response to H3 across East Asia.
