High island

In geology (and sometimes in archaeology), a high island is an island of volcanic origin. The term can be used to distinguish such islands from low islands, whose origin is due to sedimentation or uplifting of coral reefs (which have often formed on sunken volcanos).

Definition and origin

There are a number of "high islands" which rise no more than a few feet above sea level, often classified as "islets or rocks", while some "low islands", such as Makatea, Nauru, Niue, Henderson and Banaba, as uplifted coral islands, rise several hundred feet above sea level.

The two types of islands are often found in proximity to each other, especially among the islands of the South Pacific Ocean, where low islands are found on the fringing reefs that surround most high islands. Volcanic islands normally arise above a so-called hotspot.

Habitability for humans

The differences in geology and topography between high and low islands mean a lot in terms of habitability for humans: high islands above a certain size usually have fresh groundwater, while low islands often do not. This hampers or hinders human settlement on many low islands.

High Island

High Island may refer to:

See also

High Island (Queensland)

High Island, in North Queensland, Australia is part of the Frankland Islands, 30 km northeast of Babinda, and 45 km southwest of Cairns.

The Frankland Islands are teeming with permanent and migratory marine life, especially the Green Sea Turtle which nests on the island. Normanby Island, part of the Frankland Islands group, offers a comprehensive reef system with a tropical island.

The islands are very popular with reef tour operators working from Cairns.

The alternative name for this island is Caparra Island.

The island was used as a filming location in Ocean Girl.

References