Modern carbonate sedimentary facies on the outer shelf and slope around New Caledonia

International audienceWe investigated surface carbonate sediments at 33 sites on the outer shelf and slope around New Caledonia (163°–167°E, 20°–23°S), at water depths of 75–720 m. Four carbonate sedimentary facies are recognized on the basis of sediment size fractions and predominant constituents: Facies 1, encrusted grains (rhodoliths and macroids), bryozoa, and benthic foraminifera; Facies 2, bryozoa, benthic foraminifera, and mud; Facies 3, plankton and mud; and Facies 4, ahermatypic corals. Facies distributions were constrained primarily by water depth, and secondarily by local seafloor geomorphology that, in some areas, allows transport of sediments to deeper water. Because the dominant facies (Facies 1 and 3), as well as lagoon and basin facies, are distributed worldwide at similar latitudes, facies around New Caledonia can be considered as representative of carbonate sedimentary facies distributed in tropical–subtropical regions