Appendix #6: Tonga’s Islands
Located in Oceania, Tonga is an archipelago in the
South Pacific Ocean, directly south of Western Samoa
and about two-thirds of the way from Hawaii to New
Zealand. Its 176 islands are divided into three main
groups – Vava'u, Ha'apai, and Tongatapu – and cover
an 800-kilometre (500-mile)-long north-south line.
Geologically the Tongan islands are of two types: most
have a limestone base formed from uplifted coral
formations; others consist of limestone overlaying a
volcanic base.
http://en.wikipedia.org/wiki/Tonga_Islands
Source: www.tamug.educavebiologyreprintsReprint-133.pdf
Here is a graphic of the island of ‘Eau, located southeast of the main
island of Tongatapu. Its formation is typical for this island group.
Note what it is made up of:
1.
2.
3.
4.
Newer Limestone
Newer Volcanic Rock
Older Limestone
Older Volcanic Rock
Tonga’s Active Volcanoes
In 2009, Tonga experienced an amazing series of underwater volcano eruptions. Here are some
photos of the event, as well as a video clip.
Video clip: http://www.youtube.com/watch?v=ml5uolY9rFI
Picture Source:
http://scienceblogs.com/pharyngula/2009/
03/spectacular_geology_near_tonga.php