Tetiaroa Island #

Image courtesy of NASA., under PD

Tetiaroa Island is part of the Society Islands archipelago in the southern Pacific Ocean, one of several island clusters in French Polynesia. Tetiaroa is an atoll comprised of thirteen small islets (or motus).

This astronaut photograph illustrates the typical circular appearance of a fully developed atoll. The ring of islands - covered in green vegetation and white-to-tan sandy beaches - develops on coral reefs, which originally form around a volcanic island.

As the volcanic island gradually disappears due to subsidence and erosion, the coral reefs continue to grow upwards. Over time, the central volcanic island is completely submerged, leaving a ring of coral reefs and islands that surround a lagoon.

The shallow lagoon waters appear blue-green in this image, and contrast with darker and deeper Pacific Ocean waters surrounding the atoll. One of the motus in the southern portion of the atoll, Tahuna Rahi, is a protected bird sanctuary.