Major Late Pleistocene explosive eruptions of Changbaishan and Japanese volcanoes revealed by a 100-ka tephra record from the Sea of Japan

Abstract

The many subaerial volcanoes around northeast Asia have experienced frequent large- magnitude eruptions. However, many of them are not fully characterized geochronologically and geochemically, such as Changbaishan on the border between China and North Korea. We identified ten tephra layers in marine sediment cores from the Sea of Japan, confirming the occurrence of seven major eruptions around northeast Asia over the past 100 ka. Three of the tephra layers are major marker horizons around northeast Asia: AT (∼30 ka), Aso-4 (∼86 ka), and Toya (∼108 ka), which were used to constrain age models of the sediment cores. A pre-AT tephra, possibly correlative with the A-Kn eruption of the Aira caldera, was recognized in the central Sea of Japan, and it is linked to the high-resolution sedimentary record of Lake Suigetsu. The fourth Aso-4 component was recognized in this study, while component 3 was not recognized in the sediment cores from the Sea of Japan, suggesting that the eruption and tephra dispersal processes of the ∼86 ka Aso-4 eruption were complex. Additionally, one tephra layer with the age of 92.0–86.1 ka was identified in the eastern Sea of Japan; it had a similar composition to the BT-30 tephra recorded in Lake Biwa, indicating that it can serve as a new marker horizon from the Sea of Japan to central Japan. For the first time, the Changbaishan Tianwenfeng eruption was correlated with the B-J tephra from the Sea of Japan, based on a robust geochemical correlation between distal and proximal records, and was dated to 60.1–47.3/53.8–42.7 ka based on the age models of the marine sediment cores. The B-Ym tephra with an age of 87.3–81.8 ka recorded in the eastern Sea of Japan was correlated to the Changbaishan tephra, but the source eruption was not determined. These two tephra layers could be used as potential regional marker horizons when considering their thickness present in the marine sediments of the Sea of Japan.