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The monsoon system modulates surface production in the South China Sea (SCS). The winter monsoon has long been recognized as the primary factor regulating surface production in the northern SCS; however, the role of monsoon remains in debate in the southern SCS. Here, we present a long record of short-chain n -fatty acids (n -FAs) in reefal carbonates from one deep well (NK1) on an isolated coral atoll (Meiji) in order to provide new insights into the change of surface production in the southern SCS since the Late Miocene (ca. 10.5 Ma). Short-chain n -FAs indicative of total marine organic matter input are rather feasible to reflect the total production associated with mixotrophic reef-building corals that feed on various marine biotas (i.e., phytoplankton, zooplankton and bacteria). By ruling out the significant influence of diagenetic and degradation processes, short-chain n -FAs can be further applied to reconstruct paleo-production in Well NK1 coral reefs. The temporal distribution of short-chain n -FAs changes similarly with many other independent paleo-production records (i.e., Ln(Ba/Ti) and opal) in Well NK1 and adjacent ODP Site 1143, demonstrating the close coupling between coral reef production and surface water production. This occurs through the common factor of nutrients in modulating production of symbiotic autotrophic coralgae and asymbiotic phytoplankton and/or the large heterotrophic dependence of corals on phytoplankton-governed food webs in surface waters. Short-chain n -FAs inferred surface production displays a progressively decreased trend from the Late Miocene to Pliocene (ca. 10.5–2.6 Ma) followed by a substantial increase since the Pleistocene on million-year timescales, which follows the variation of terrigenous supply to the coral atoll and responds almost inversely to the sea-level change. Accordingly, we propose that long-term paleo-production in the southern SCS was associated with terrestrial nutrient input which was controlled by relative sea-level change since the Late Miocene. This study highlights the feasibility of short-chain n -FAs as appropriate production recorders in shallow-water coral reefs which are widespread in tropical-subtropical oceans, providing valuable perspectives on long-term paleo-production evolution in surface waters. • A long coral reef well (NK1) in the southern SCS was studied. • OM-poor coral reef carbonates were decalcified and extracted for biomarkers. • Short-chain n -FAs reflect paleo-production in coral reefs since the Late Miocene. • Long-term production was governed by terrestrial nutrient related to sea level. [ABSTRACT FROM AUTHOR]

Cyprus is one of the few areas of the Mediterranean where lower and upper Miocene coral-reefs occur in close proximity and is thus well suited to investigate how environmental and geological changes affected the reefs and their associated shallow-marine facies. The prevailing environmental conditions of the lower Miocene Terra Member and of the upper Miocene Koronia Member are reconstructed here, using detailed microfacies comparisons of the skeletal, foraminiferal and calcareous algal assemblages. The lower Miocene reefs are characterised by a higher biodiversity of coralline algae, large benthic foraminifera and corals, and mainly developed in slightly deeper water (20–40 m, lower euphotic zone) than the upper Miocene reefs (< 15 m; upper euphotic zone). The reduced late Miocene biodiversity was probably caused by changes in the Mediterranean marine environment (e.g. increased seasonality), possibly in response to global cooling, increased latitudinal gradients and progressive isolation of the basin. The observed shift of the reef environment towards the upper euphotic zone could be explained as a response to late Miocene physical oceanographic setting, notably temperature changes, which could have made the upper euphotic zone more favourable for certain hermatypic corals. Similarities between the Miocene carbonate facies of Cyprus and the Eratosthenes Seamount directly to the south, and elsewhere in the Mediterranean region (e.g., Corsica; Italy; Spain), suggest that the environmental changes inferred for the Miocene of Cyprus operated on a Mediterranean or even wider scale. • The skeletal assemblages of Miocene neritic carbonates of Cyprus are analysed. • Lower Miocene coral-reefs are highly biodiverse and developed between 20 and 40 m of water depth. • Upper Miocene coral-reefs display a low biodiversity and developed <15 m of water-depth. • Biodiversity decreased in response to less favorable conditions in the late Miocene. [ABSTRACT FROM AUTHOR]

The Western Australian margin is a unique coral reef province, with modern coral reef development occurring at latitudes as far south as 29°S. The genesis of this coral reef province may go back to the Oligo-Miocene, since geological features ~30 million-year-old and younger interpreted as coral reefs are known from offshore seismic surveys. The nature of these seismic reefs is, however, uncertain, as they are only sparsely sampled, and as time-equivalent outcrops are only present in a few remote and understudied locations. This study investigates middle Miocene shallow-water limestones with tropical fauna formed along the North West Shelf (NWS) between ~13 Ma and ~15 Ma, when the southward extension of the seismic reefs was at its maximum. The outcrops and cores investigated are dominantly composed of peloidal packstones and micritic floatstones containing larger benthic foraminifera, Halimeda sp. and scleractinian corals, including reef-building genera, that accumulated in a protected and oligotrophic, warm-water lagoonal environment. Climate was therefore warm during the middle Miocene acme of seismic reefs development, despite the NWS being located ~7° further south than its present position at that time. Results of this investigation also support the existence of a strong southward flowing Leeuwin-current-style oceanic circulation during the middle Miocene, which could have transported fauna from south-east Asia along the Western Australian margin. Development of the lagoon and seismic reefs may have also been promoted by middle Miocene aridification of the coast bordering the NWS, and by repeated eustatic-driven exposures of the NWS. [Display omitted] • Lagoon 15–13 Ma with taxa characteristic of tropical oligotrophic reef environments • Facies with micrite, scleractinian corals, Halimeda and larger benthic foraminifera • Outcrops time-equivalent to offshore Middle Miocene Western "Great Barrier Reef" • Time-equivalent to Miocene Climatic Transition, post-date Miocene Climatic Optimum • Climatic, paleoceanographic (proto-Leeuwin current), eustatic or tectonic controls [ABSTRACT FROM AUTHOR]