AbstractA sediment core from Trullvatnet, a lake at 1 m a.s.l. in the inner Murchisonfjorden area, northwestern Spitsbergen, was examined. The sediments in the 3 m-long core cover a period of about 7000 C14years and show a sequence of two marine-lacustrine contacts in the lower region. The renewed connexion with the sea of the basin between 5500±140 and 4745±120 C14years ago, followed by a final isolation, suggests an interruption in the general negative trend of shoreline displacement.