The underwater volcano Kikai-Acahuia has been responsible for three major eruptions in the past 140,000 years. The last of these events occurred 7,300 years ago south of the Japanese island of Kyushu, where the Philippine tectonic plate meets the Eurasian plate. The explosion was already known, but researchers have now discovered that it was the largest ever recorded in the planet's history.
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According to researchers, the eruption released more than twice the amount of rock and ash compared to the 1815 eruption of Mount Tambora in Indonesia, which is considered the most powerful to date.
In the new study, the team collected seismic data to create a detailed map of the seafloor around the Kikai-Acahuya volcano. The work revealed huge underwater deposits that were excavated at several points using a remote-controlled robot. The extracted sediment cores were then analyzed.
The material revealed a 4,500-square-kilometre layer of volcanic glass consistent with the composition and timing of the Kikai-Acahuya eruption. Debris totaled about 71 cubic kilometers of material thrown out to sea by the eruption, nearly double estimates published in previous research.
The researchers combined these results with existing estimates of the volcanic debris resulting from the eruption that was deposited on Earth. They found that the massive eruption spewed a total volume of 332 to 457 cubic kilometers of lava, enough to fill Lake Tahoe in the western United States twice.
The largest eruption of the Holocene epoch
- The new study indicates that the Kikai-Acahuia eruption is “most likely the largest eruption of the Holocene,” a geological epoch that began 12,000 years ago, at the end of the last ice age, and in which we still live today.
- The researchers also concluded that the explosion was larger than that of the Santorini volcano.
- However, it lags behind ancient events.
- This is the case with the catastrophic eruption of the giant Toba volcano, in Sumatra, 74 thousand years ago, which released about 5 thousand cubic kilometers of magma.
- The study was published in Journal of Volcanology and Geothermal Research.
- Information is from Live sciences.
