Nevado del Ruiz' ashes prompt closure of Colombian Airport - submarine volcano erupts near Tonga

© El Espectador

The increase in the emissions of ashes from Colombia's volcano Nevado del Ruiz prompted today the closure of nearby La Nubia airport to prevent traffic congestion to and from the terminal. According to Director of the Volcano Observatory of Manizales, Gloria Cortes, the communities near the crater, the most watched over in Colombia, remain on alert because of this increase in its activity.

The measure to suspend operations in the terminal was adopted to prevent any air accident because the ashes might interfere with the good functioning of plane turbines. Besides, the volcano, located between the central departments of Caldas and Tolima, continue emitting sulfure dioxide, though for the time being the situation is not serious, said Cortes as quoted by El Espectador newspaper.

Located 220 km west of Bogota, is part of the volcanic strip of Los Andes, also including another 74 similar structures. Its first eruptions occurred 1.8 million years ago, in the early Pleistocene, but the most lethal explosion was registered in November, 1985, when an enormous lahar (mud and debris flow) buried the small town of Armero, in Tolima, in Lagunilla valley, where only one fourth of its 28,000 inhabitants managed to survive in the absence of early warnings or predictions. Chinchina town also suffered the impact of the phenomenon, losing nearly 2,000 inhabitants. -

Submarine volcano erupts near Tonga

Activity continues, but seems not to have breached the surface (for now). Recent satellite imagery with clear views show a discolored water plume and a steam plume but no ash, suggesting that that the activity is still well below the surface. Hunga Ha'apa and Hunga Tonga islands are subaerial parts of a large caldera of about 6 km diameter. A number of cones have been built near its rim during past eruptions, including the Hunga Ha'apa and Hunga Tonga islands themselves.

The eruption of 1988 took place from a fissure on the Hunga Ha'apai cone near the south rim of the caldera. Being at 200 m depth, it remained completely under water; only single pumice and scoria blocks floated to the surface during the eruption. The eruption in 2009 took place again from the Hunga Ha'apai volcano, but this time the fissure cut trough the island and occurred in shallow water, producing spectacular surtseyan explosions. The current eruption seems to occur from another location, again at deeper water depth: judging from the origin location of the steam plume, its vent is likely on the NE base of the submarine base of Hunga Ha'apai island, or on the valley separating it from Hunga Tonga island to the NE. -