Edgecumbe

sopka – Volcanic field, United States, North America Volcanic Regions

Kde

United States, North America Volcanic Regions

Typ (GVP)

Volcanic field

Nadmořská výška

970 m

Tektonické prostředí

Intraplate / Continental crust (> 25 km)

Poslední známá erupce

2 080 př. n. l.

Poloha

57,050°, -135,750°

The Edgecumbe volcanic field covers about 260 km2 of Kruzov Island west of Sitka in SE Alaska. The basaltic-to-dacitic field is dominated by the large composite cones of Mount Edgecumbe, Crater Ridge, and Shell Mountain. This Pleistocene-to-Holocene system is 16 km E of the Queen Charlotte-Fairweather transform fault separating the North American and Pacific plates. Mount Edgecumbe is a stratovolcano with a well-defined crater, and is the largest edifice of the field. Crater Ridge is truncated by a 1.6-km-wide, 240-m-deep caldera. These and other vents are oriented along a SW-NE line. Volcanic activity originated about 600,000 years ago along fissures cutting Kruzof Island. A series of major silicic explosive eruptions took place about 9,000-13,000 radiocarbon years ago. The latest dated eruptions were phreatomagmatic explosions during the mid-Holocene, and all postglacial activity has been pyroclastic. Reports of observed eruptions are unsubstantiated.

Text: Smithsonian Global Volcanism Program.

Údaje o sopce: Smithsonian Global Volcanism Program. Další sopky a průduchy.