Biogenic sediments on the Eauripik Rise of the western equatorial Pacific during the late Pleistocene

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It has been suggested that late Quaternary variability in atmospheric CO₂ concentrations may have resulted from variations in the nature of biogenic sedimentation. In this paper we present 262 kyr time series for the mass accumulation rates of organic carbon (MAR_OC), carbonate (MAR_Carbonate), and biogenic opal (MAR_opal) of the Eauripik Rise, the western equatorial Pacific. The MAR_OC record exhibits a general trend of higher values during glaciation time; Stage 2, Stage 3, Stage 4, Stage 6 and late Stage 8 except middle Stage 5. A weak correlation between MAR_OC and MAR_opal as well as MAR_Carbonate is attributed to the oligotrophic character of the western Pacific in the Eauripik Rise area. Spectral analysis of organic carbon contents displays eccentricity, obliquity and precession-related peaks. The presence of 23-kyr periodicity indicates a possible link between organic carbon burial and trade winds associated with insolation.