[4][5][6]: 100 There is evidence of volcanic activity at the Kikai Caldera in what is termed the K–Km tephra layers between 16–9 cal ka BP.

[7]: 336  The Takeshima debris avalanche followed by the Nagahama lava (NgL) and Heikejo ash (K–Hj) events preceded the eruption.

[2] The eruption was partially submarine and a fuller understanding of its character required the realisation that part of the pyroclastic density current had been transformed into a subaqueous density current that contributed to a total seafloor deposit volume of 71 km3 (17 cu mi).

[7]: 337  The depth of some of the eruption is important as seafloor-hugging density currents are not described in shallow underwater settings.

[8]: 224  Until the presence of a subaqueous density current was understood a VRE of 7.2 had been estimated,[1] with a total DRE volume of 70–80 km3 (17–19 cu mi)[8]: 234  Sea level would have been lower than present at the time of the eruption but would have reached present levels within a thousand years.

[14][15][1] This eruption has been linked to the end of the initial Jōmon culture in southern Kyūshū although impact, although marked, was not as great as some commentary had suggested with Nishinozono sub-type pottery tradition, that had started prior maintained throughout and after the eruption sequence in Kyūshū.

[17] Jōmon who lived further away survived such as on northern Kyūshū, Honshū and Hokkaidō but likely had to revert for a period to maritime food sources mainly.

[16] The fate of the initial Jōmon culture on south Kyūshū does not quite parallel the demise of the Minoan civilization, which may have ended as a consequence of another massive volcanic eruption.