Page 346 - Volcano and Geothermal Tourism

Case Study 17

Vanuatu

Active Volcanism in the Pacific

Henry Gaudru simply because it is so easy to reach. Each year the
Yasur volcano attracts near 3000 visitors. Tour
Introduction operators make a good business in volcano tours
although it’s easy to visit independently. Tourists
Vanuatu (formerly called the New Hebrides can travel up this volcano in a four-wheel drive
Islands) is a line of volcanic islands and submarine from Lenakel to just near the top and then walk
volcanoes 2,300km east of north-east Australia. to the edge of the crater and peer down at the
There are 13 main islands, 9 of which are home to seething mass of bubbling magma. Although Yasur
active volcanoes. Present day volcanism is related is active year round, it is unusual for it to be too
to the north-eastward directed subduction of the active to approach so it has become an extremely
Australian Plate beneath the edge of the Pacific popular tourist attraction. Yasur usually has at least
Plate. The two plates converge at a rate of about 50 people or more on top during most evenings
9cm/year. A divergent plate boundary (called a in the high season (June to September). When
spreading centre or spreading axis) is east of Captain Cook first sighted Yasur in 1774, he
Vanuatu (Monzier et al, 1997). The main active likened it to Stromboli in the Mediterranean
volcanoes are: Yasur volcano, one of the world’s because of its constant glow at night, like a beacon.
most active with Strombolian eruptions occurring In fact, Yasur often erupts with Strombolian type
many times per hour; Lopevi volcano, a perfect eruption, throwing out incandescent ejecta or lava
volcanic cone located in a beautiful South Pacific fountains from a central crater, but also can
setting; Amrbym volcano, with a large caldera sometimes show a Vulcanian type of eruption. In
including two cones with lava lake; and Gaua this case large blocks and glowing fragments of
volcano, with one of the world’s most colourful new, viscous lava are thrown out and this is what
and scenic multi-coloured summits and a crater most people see when they stand on the edge of
lake which creates an unforgettable landscape. the Yasur and look in.
Ambae volcano erupted in December 2005 after Generally, the blocks are not thrown too high
being dormant for 120 years (Seach, 2009).
so it is not dangerous. For those living on the
Yasur volcano island, it is common knowledge that Yasur seems
most active around late February to April. This
Yasur volcano on Tanna Island is an active cone, time of year is the wet season. A lot of rain means
365m in elevation, with a base about 1.5km wide. a higher groundwater table, possibly allowing
This is the youngest of several small volcanoes water to come into contact with hot rocks around
which occupy the Siwi area. Yasur is one of the the magma chamber. Explosive phreatic eruptions
most famous volcanoes in the Oceania region, are known to occur sometimes, but whether this

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