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We collected and dated fossil corals from the uplifted reef tracts of Sumba Island. Mass spectrometry (TIMS and AMS) was used to obtain reliable and precise radiochronological results. It is possible to identify outcrops corresponding to major sea level high stands: isotope stage 1 (starting at 7.1 kyr BP), 5a (c.a. 86 kyr BP), 5c (c.a. 105 kyr BP), 5e (between 119 and 132 kyr BP) and 9 (c.a. 305 kyr BP). The radiochronological data are thus broadly consistent with the timing of sea level fluctuations predicted by the astronomical theory of paleoclimates. Comparison with similar data from other terrace sequences and from benthic δ18O records indicates that the average tectonic uplift rate at Cape Laundi, Sumba, is on the order of 0.2–0.5m/kyr. The lowest values (<0.3m/kyr) lead to the build‐up of polycyclic topographic terraces in which it is possible to find corals grown during different interstadial or even interglacial times.

The sedimentological and chronological study of Holocene reef sequences recovered in drill cores through modern reefs of Mauritius, Re´union Island and Mayotte allows the reconstruction of sea level changes and reef growth patterns during the Holocene. The branching-coral facies systematically predominates over coral head facies throughout the Holocene reef sequences, and Acropora is the main frame builder among the branching forms. The reconstructed sea level curves, based both on identification of coral assemblages and on radiometric U/Th ages, are characterized by a rapid rise between 10 and 7.5 ky BP, followed by a clear inflection between 7.5 and 7 ky BP. The stabilization of sea level at its present level occurred between 2000 and 3000 years ago, probably without a higher sea level stand. Rates of vertical reef accretion range between 0.9 and 7 mm. y\.

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