| Country: | Japan | ||
| Subregion Name: | Kyushu (Japan) | ||
| Volcano Number: | 0802-10= | ||
| Volcano Type: | Complex volcano | ||
| Volcano Status: | Historical | ||
| Last Known Eruption: | 1996 | ||
| Summit Elevation: | 1500 m | 4,921 feet | |
| Latitude: | 32.757°N | 32°45'24"N | |
| Longitude: | 130.294°E | 130°17'40"E | |
| The massive Unzen volcanic complex comprises much of the Shimabara Peninsula east of the city of Nagasaki. A 30-40-km-long, E-W-trending graben extends across the peninsula. Three large stratovolcanoes with complex structures, Kinugasa on the north, Fugen-dake at the east-center, and Kusenbu on the south, form topographic highs on the broad peninsula. Fugen-dake and Mayu-yama volcanoes in the east-central portion of the andesitic-to-dacitic Unzen volcanic complex have been active during the Holocene. The Mayu-yama lava dome complex, located along the eastern coast west of Shimabara City, formed about 4000 years ago and was the source of a devastating 1792 AD debris avalanche and tsunami. Historical eruptive activity has been restricted to the summit and flanks of Fugen-dake. The latest activity during 1990-95 formed a lava dome at the summit, accompanied by pyroclastic flows that caused fatalities and damaged populated areas near Shimabara City. | |||