The launch of a new GVP website is scheduled for Monday, May 20, 2013.
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Country: | Japan | |
| Subregion Name: | Honshu (Japan) | ||
| Volcano Number: | 0803-271 | ||
| Volcano Type: | Caldera | ||
| Volcano Status: | Historical | ||
| Last Known Eruption: | 915 AD | ||
| Summit Elevation: | 1159 m | 3,802 feet | |
| Latitude: | 40.47°N | 40°28'0"N | |
| Longitude: | 140.92°E | 140°55'0"E | |
| The dramatic, 11-km-wide, lake-filled Towada caldera formed during as many as six major explosive eruptions over a 40,000-year period ending about 13,000 years ago. Pre-caldera eruptive activity at Towada dates back to about 2 million years ago and produced basaltic-to-dacitic lava cones. Following late-Pleistocene andesitic-to-rhyolitic caldera-forming eruptions, the basaltic Ninokura stratovolcano grew in the SSE section of the caldera. The successive dacitic-to-rhyolitic Goshikiiwa explosive eruptions led to the formation of the roughly 2-km-wide Nakanoumi caldera, whose SW and NE rims form dramatic peninsulas extending into Lake Towada. The andesitic-to-dacitic Ogura-yama lava dome was built over the NE rim of Nakanoumi. The latest eruption of Towada took place in 915 AD, when eruptions from Ogura-yama produced widespread ashfalls and pyroclastic flows. | |||
