Page 37 - Volcano and Geothermal Tourism

14 Introduction

• Mud volcanoes – similar to magma volcanoes, • Volcanic field (Auckland VF, New Zealand;
they can erupt by channelling boiling water, Oku VF, Cameroon; Tuya VF, British Columbia/
steam or pressurized gas to the surface. They Canada; Clear Lake VF, California).
can be related to oil and gas reserves and • Volcanic fissure – fissure vent, fissure volcano,
sometimes erupt in flames (Gallagher, 2003) linear or elongated fracture of the ground from
(Iran, Indonesia, Japan, New Zealand, Russia, which lava, pyroclastics or gas are erupting, can
Italy, China, Pakistan, Romania, Canada, North be up to several kilometres long (Krafla, Eldgjá,
America, Colombia, Venezuela). Laki – Iceland; Hawai‘i; Great Rift Valley;
• Moberg or tuya – see sub-glacial volcano. Tobalchik – Kamchatka; Ethiopia; Komagatake – Japan).
• Pseudo craters – also known as rootless • Volcanic rift – a region marked by volcanic
cones formed by exploding steam when lava action, e.g. long linear cracks in the Earth’s crust
flows over wetlands (Skútustaðagígar, Iceland). which occur where magma reaches the surface
• Rift valley – see volcanic rift. (Ritchie and Gates, 2001) (Canary Islands; Hawai‘i;
• Shield volcanoes – built mainly from multi- Iceland; East African Rift; Tonga Arc; Antarctica).
directional lava flows of Hawaiian type
eruptions into gently sloping landforms The volcanic features listed above include quite a
comparable to a broad shield (Mauna Loa, few interesting volcanic destinations for tourists,
Mauna Kea, Hawai‘i; Cascades, Oregon; Erta Ale, although not all of them are accessible to the
Ethiopia; Easter Islands; Hierro, Canary Islands; general public – for example, submarine
Skjaldbreiður, Iceland; Newer Volcanic Provinces, hydrothermal vents or black smokers. Fascinating
Australia; Santorini, Greece; Tolbachik , Kamchatka; as the latter are, access to these is only possible via
Rangitoto, New Zealand; Fernandina, Galapagos). submersible observation crafts, which are in the
• Sub-glacial volcano – table mountain exclusive service of science.
created by a volcanic eruption underneath a Besides volcanic landforms, geothermal features
–
glacier (Tuya Butte, Canada; Herdubreid, Iceland; are visual attractions in their own right and are
Viedma, Argentina). commonly found either in the neighbourhood of
• Sub-marine or subaqueous volcanoes – volcanoes, both active and dormant, or they
occur frequently along mid-ocean ridges, originate from artesian springs and bores (e.g.
sometimes producing islands (Surtsey – Iceland; Guarani Aquifer, South America; Great Artesian
Hawaiian Emperor Seamount Chain; Tonga – Basin, Australia). Hot springs do not need magma
Home Reef). bodies to acquire their high temperatures. As water
• Super volcanoes – according to some passes through subterranean rocks, the geothermal
scientists it is only a matter of time until one temperature gradient combined with time and
of them will erupt and cause a disaster of great pressure at depth play a role in the formation of
magnitude (Cas, 2005; Watts, 2007) (Mt Toba, hot springs rich in minerals and metallic trace
Sumatra/Indonesia; Aniachak, Alaska; Taupo, New elements. The effects of heated rocks below the
Zealand; Yellowstone, Wyoming; Tambora, Indonesia; surface can cause a number of processes, some of
Vilama Caldera, Argentina/Central Andes). which manifest themselves as geothermal
• Volcanic arc – chain of volcanic islands, usually phenomena such as hot springs, fumaroles, geysers,
with strong seismic activity related to underlying boiling lakes, heated streams and bubbling mud
tectonic processes (Japanese island chains; Aleutian ponds (Erfurt-Cooper and Cooper, 2009, pp130–
Volcanic Arc; Marianas Arc; Kuril Island Arc; Lesser 155). Some examples below highlight the most
Antilles; Kermadic Islands; Tonga Islands; Sunda interesting geothermal features with some examples
Island Arc; Solomon Islands; Philippine Islands). of destination countries:
• Volcanic belt – region of volcanic and
geothermal activity (Pacific Ring of Fire; Garibaldi • geysers (Iceland, New Zealand, USA, South and
VB, Canada; Andean VB; Trans-Mexican VB; Central America, Japan);
Taupo VB; Okhotsk-Chukotka VB; Pontide VB, • boiling lakes and ponds (Japan, USA, New
Turkey; Wrangell VB, Alaska; Central Iranian VB). Zealand, Iceland);

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