retour au sommaire de SUDS EN LIGNE
Les différents types de volcansLes risques majeursDes outils de diagnosticLa gestion des crisesEquateurVanuatuChiliCamerounliens utiles

Tanna  |  Ambae  |  Karua  |  Ambrym  |  Lopevi  |  Gaua  |  Epi

Karua, a volcano born out of a cataclysmic event

After Kuwae: Karua 
Cyclic fumarole activity
  |  500 years of oral tradition

After Kuwae: Karua

The submarine volcano Karua grew in the gigantic caldera (60 km2) left by the cataclysmic eruption of Kuwae in 1450. The base of the current volcanic structure lies at a depth of 400m below sea level. It reached the surface in 1897, and again in1900/1901. Fresh activity was observed in 1923 and 1925, and in 1948 it rose above the ocean to form an island, 100 m high and about one and a half kilometres across. In 1950 the island sank, only to emerge again in 1959 and 1971.  This latter structure remained an island until 1975. Between these periods, frothing  and discoloration of the water were frequently observed. The summit area of the volcano, a vast flattish plateau lying at a depth of about 12 metres, was photographed and filmed in 1997 during an observation cruise carried out by IRD as part of a general programme of study and monitoring of Vanuatu's volcanoes. Its continuing activity is evidenced by the production of gasses. IRD's divers noted the presence of a few algae, and many small invertebrates (alcyonarians, ascidians, starfish) attached to smallish rocks lying on a bed of reddish or grey ashes.

retour au sommaire des volcans Vanuatu en français Vanuatu in English