Age of the Tahitian Coral Reefs

Abstract

DR. CYRIL CROSSLAND (NATURE, Oct. 12, p. 576) refers to my discovery of coral fragments in a parasitic tuff-cone at Tataa Point, at the north-west corner of Tahiti. The size and water-worn character of these fragments and of the associated basaltic pebbles in the tuff suggest that the cone was built by eruptions through an old beach sprinkled with coral debris. Had the eruption burst through a solid reef, it may reasonably be supposed that large angular blocks of coral would be found. Dr. Wayland Vaughan and Dr. J. E. Hoffmeister agree as to the age of the corals. The latter writes: “Most of the fragments seem to belong to Porites, two to Acropora, two to Pavona and two to Pocillopora. The Pavona is of the same type as P. duerdeni, Vaughan, or P. maldivensis (Gardiner), which are common in the Pacific of to-day. As Dr. Vaughan has said, there is nothing in this collection which might lead one to suspect that they are older than Pleistocene.” He adds that among a collection of recent corals, made by Prof. Setchell, from the barrier reef off Papeete Harbour, he can find none common to the Tataa fauna.