Raoul Island

sopka – Stratovolcano, New Zealand, Tonga-Kermadec Volcanic Regions

Kde

New Zealand, Tonga-Kermadec Volcanic Regions

Typ (GVP)

Stratovolcano

Nadmořská výška

516 m

Tektonické prostředí

Subduction zone / Oceanic crust (< 15 km)

Poslední známá erupce

2006

Poloha

-29,270°, -177,920°

Anvil-shaped Raoul Island is the largest and northernmost of the Kermadec Islands. During the past several thousand years volcanism has been dominated by dacitic explosive eruptions. Two Holocene calderas exist, the older of which cuts the center the island and is about 2.5 x 3.5 km wide. Denham caldera, formed during a major dacitic explosive eruption about 2200 years ago, truncated the W side of the island and is 6.5 x 4 km wide. Its long axis is parallel to the tectonic fabric of the Havre Trough that lies W of the volcanic arc. Historical eruptions during the 19th and 20th centuries have sometimes occurred simultaneously from both calderas, and have consisted of small-to-moderate phreatic eruptions, some of which formed ephemeral islands in Denham caldera. An unnamed submarine cone, one of several located along a fissure on the lower NNE flank, has also erupted during historical time, and satellitic vents are concentrated along two parallel NNE-trending lineaments.

Text: Smithsonian Global Volcanism Program.

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