Holocene lagoonal sedimentation at the latitudinal limits of reef growth, Lord Howe Island, Tasman Sea

Abstract

The southernmost limit to coral reef growth occurs on Lord Howe Island (33°30'S, 159°05'E) where a discontinuous fringing reef flanks the western side of the island. Coring and radiocarbon dating indicate that carbonate sediments were first deposited within the lagoon around 6500 radiocarbon years BP coincident with sea level reaching close to its modern level. High-energy conditions dominated the reef with robust branching corals dominating the developing reef. Growth of the reef crest between 6000 and 5000 yr BP is inferred to have caused a reduction in the energy conditions within the lagoon resulting in mud deposition. During this period, sedimentation occurred at average rates of around..