Abstract
The specific activities of 226Ra and 210Pb in six sediment cores from the Nansha sea area were measured by high-purity germanium spectroscopy. Based on the data of 210Pbex at different depths, the sedimentation rates of six cores of NS-1 ~ NS-6 after compaction correction were calculated to be 0.39 ± 0.04, 0.65 ± 0.06, 0.39 ± 0.03, 0.31 ± 0.03, 0.33 ± 0.06 and 0.28 ± 0.02 (cm·year−1), respectively. Combined the organic carbon contents measured by the volumetric method with the sedimentary mass flux, the sedimentation fluxes of particle organic carbon at NS-1 ~ NS-6 stations were calculated to be 3.26 ± 0.05, 6.91 ± 0.12, 3.46 ± 0.09, 5.19 ± 0.07, 5.47 ± 0.11, 4.47 ± 0.09 (mmol C·m−2·d−1), respectively.
Graphic abstract
Using the natural logarithm value of 210Pbex in each section of sediment core, the sedimentation rates between two layers in each cores were calculated. Through the linear fitting of core depth and natural logarithm value of 210Pbex, the average sedimentation rates (cm× yr-1) of six sediment cores from NS1~ NS6 were calculated to be 0.39±0.04, 0.65±0.06, 0.39±0.03, 0.31±0.03, 0.33±0.06 and 0.28±0.02, respectively. 