Sedimentation Rates in Puget Sound from (210)Pb Measurements

摘要

Sixteen (210)Pb profiles from sites along the axis of the Main Basin of Puget Sound show that bottom sediments are accumulating at rates of 0.26 to 1.20 g/sq cm/yr; these along with seven rates earlier published suggest highest accumulation nearly midway along the length of this tidal current-dominated basin. Bioturbated surface layers of cores have also been found to be as deep as 40 cm, but biologic mixing rates are poorly determined. Individual (210)Pb accumulation rates have a range of from approximately one to five times areal average accumulation rates based on estimates of recent sediment input from riverine and shoreline sources.