Akita-Komagatake (Japan): Recorded Eruptions and Historical Activity

Akita-Komagatake is a stratovolcano located in Japan at an elevation of 1,637 meters, situated within a subduction zone and continental crust tectonic setting. Official records from the Smithsonian Global Volcanism Program document a total of 18 confirmed eruptions spanning from prehistoric periods to the 20th century CE.

Eruption History and Chronology

The historical and prehistoric record for Akita-Komagatake includes 18 confirmed eruptions. These events stretch across multiple millennia, utilizing various evidence methods such as tephrochronology, calibrated radiocarbon dating, and direct historical observations. The earliest recorded eruption in the collection began around 8800 BCE with an estimated start year uncertainty of 300 years and a Volcanic Explosivity Index (VEI) of 3.0. Other early examples include an eruption starting around 7850 BCE with a VEI of 4.0 and an uncertainty of 200 years, and an event around 6350 BCE with a VEI of 3.0 and an uncertainty of 200 years.

Centuries later, activity continued with occurrences such as an eruption around 350 BCE with a VEI of 3.0 and an uncertainty of 200 years. More recent historical documentation includes an eruption at the Me-dake activity area that began on September 18, 1970, and ended on January 26, 1971, with a VEI of 2.0 based on reported observations. Across the complete confirmed eruption record, the largest recorded Volcanic Explosivity Index is 4.0.

Distribution of Activity by Century

The 18 confirmed eruptions are distributed across various centuries and millennia BCE and CE. The collection records activity in the following timeframes: the 88th century BCE (1 eruption), 83rd century BCE (1 eruption), 79th century BCE (1 eruption), 71st century BCE (1 eruption), 64th century BCE (1 eruption), 62nd century BCE (1 eruption), 60th century BCE (1 eruption), 4th century BCE (1 eruption), 2nd century BCE (1 eruption), 1st century BCE (1 eruption), the 4th century CE (1 eruption), 9th century CE (1 eruption), 11th century CE (1 eruption), 15th century BCE (1 eruption), and the 20th century CE (3 eruptions). Out of the 18 total confirmed eruptions, 13 have recorded Volcanic Explosivity Index (VEI) values.