This study assesses patterns of biogenic carbonate sediment production associated with three different reef and reef-related settings at Danjugan Island in the Philippines. Sediments were collected along transects on windward and leeward sides of the island (1–28-m depth) and from a semirestricted lagoon (1.5–2.5-m depth). Sediment assemblages from all sites are dominated (in decreasing order of abundance) by coral (29.1%), Halimeda (28.8%), mollusks (13.5%), and benthic foraminifera (10.2%). Sediments from windward sites are dominated by fragments of corals (15.0–42.5%), Halimeda (14.0–32.1%), mollusks (8.5–21.6%), and benthic foraminifera (7.8–32.9%). Bryozoans represent a significant secondary component (2.77–14.6%). Leeward sediments primarily comprise coral, Halimeda, and molluscan grains, although are characterized by a higher abundance of Halimeda (29.7–49.2%) than the windward transect. Lagoon sediments comprise primarily coral (1.3–42.7%) and Halimeda (13.8–37.2%) in the outer lagoon, but a high proportion (29.8–61.8%) of fine-grained unidentified detrital (probably terrestrially derived) material at inner lagoon areas. Across each transect, sediment compositional and textural characteristics exhibit marked bathymetric variations. Coral, Halimeda, benthic foraminifera, and mollusks dominate windward and leeward reef flats, whereas coral and Halimeda dominate deeper reef-slope settings. Mean grain size generally decreases with depth and sorting increases with depth. Multivariate analysis of percentage similarity delineate the following facies groupings; windward and leeward reef slopes, windward and leeward reef flats, and inner and outer lagoon. These assemblages are likely to reflect not only rates of production by individual sediment contributors but also subsequent physical reworking of grains and the preferential transport of more buoyant sediment particles.

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