The central Arctic Ocean sediment record: current progress in moving from a litho- to a chronostratigraphy

Abstract

In recent years there has arisen a major controversy surrounding the ages of the sediments recovered from the central Arctic Ocean. Earlier interpretations (Steuerwald et al. 1968; Clark 1970. 1971; Hunkins et al. 1971; Clark et al. 1980) inferred that the rates were very low, and of the order of 0.2 to 0.005 cm/ 1,000 years. These ages were based primarily upon published interpretations of the paleomagnetic polarity records of central Arctic Ocean sediments. These interpretations have been challenged by Sejrup et al. (1984). These authors measured amino acid D/L ratios of planktonic and benthonic foraminifera in core T3-67-11. They interpreted their results to mean that central Arctic Ocean sedimentation rates were 10 to 20 times higher than had been previously reported. These authors pointed out that since the actual paleomagnetics data had only been published from one Arctic Ocean core, the published polarity interpretations could not be fully evaluated. Jansen et al. (1983) and Zahn et al. (1985) have looked at the stable isotopic composition of planktonic foraminifera and the paleomagnetic records from cores to the north of the Fram Strait and within the Norwegian-Greenland Sea and suggested that the low sedimentation rate interpretations previously put forth could indeed be in error.