Sediments accumulate in the Santa Barbara Basin relatively rapidly: about 3–4 mm yr−1 based on the analysis of varves. These deposits are ideal for studying the applicability of nuclear geochronological techniques in a natural situation. Studies of the depth distribution of several radionuclides, manmade 55Fe and naturally occurring 210Pb and Th isotopes, in recent Santa Barbara sediment layers permit an evaluation of the geochemical behavior of Fe, Pb, and Th in coastal waters and have established the usefulness of 55Fe and 210Pb for dating coastal or near coastal sediments deposited during the last decade and half‐century respectively.