CURRENT RATES OF SEDIMENTS ACCUMULATION AT THE SHELF OF WESTERN EQUATORIAL AFRICA NEAR THE KONGO MOUTH

Mean sedimentation rates Of bottom sediments, sampled during the 20th voyage of the r/v ''VIT.YAZ'' in the site located on the shelf, near t he Kongo mouth, have been determined. The unbalanced Pb-210 method thr ough constant concentration model was used. The distribution of Pb-210 has been analyzed in a total of 16 stations, positioned both at the b ottom of the canyon which is the continuation of the Kongo river bed, and on its shoulders. At the bottom of the canyon, at the depth of 1 k m redeposits can be determined from the sides of the canyon bottoms (i n the examined 12 - 15 cm sediment monoliths), which are characterized by high concentration values of Pb-210. Sedimentation rates of superf icial layer of the sediments vary within the range between 0.065 and 0 .290 cm per year; with the mean value of 0.141 +/- 0.083 cm/year. At m ost stations the analysis of Pb-210 distribution indicates the presenc e of redeposited substanse. Five stations were marked by the level of Pb-210 integral activity. They are characterized by a close to the acc epted pattern of sediments accumulation. The sedimentation rates for t hese 5 stations are 0.082 +/- 0.024 cm/year.