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1979
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Jean-Pierre Chevalier et al., « Géomorphologie de l'atoll de Takapoto », Journal de la Société des Océanistes, ID : 10.3406/jso.1979.2988
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This study covers the different parts of the atoll: atoll rim (outer reef flat, elevated reef, inner reef flat) and lagoon. The rim is an almost continuous island, made of an old reef conglomerate which emerges of 50 cm above the sea level (low tide) and on which recent and gravel formations are deposited; Beachrocks appear in some areas. The outer reef is constituted by a reef flat, an algal ridge which is crossed by many grooves, and an outer slope. The appearance of the edge of the reef differs according to the reef position with regard to the winds. There are very few functional channels (hoa) between the ocean and the lagoon, all situated near Teavatika, or Takaï. The inner reef flat often shows gravel or sandy accumulations more or less covering the old reef conglomerate. In the center of the lagoon, there are many patch reefs, surface-rising patches or knolls, which were built when the sea-level was higher than it is now. To day, building fauna is scarce.