SEDIMENTARY SILOXANES - A GEOCHRONOLOGICAL STUDY

Selected samples of sediments from cores taken in the Ala Wai Canal (s outh-east Oahu, Hawaii) have been analyzed for organosilicon (silicone ) content, Observed levels of silicone range from just above the detec tion limit (similar to 0.01 ppm) to over 1 ppm, and vertical distribut ion in the sediment column generally increases upwards, with the highe st silicone content in the most contemporary sediments (dated independ ently by Pb-210 and Cs-137 measurements), Further, there is clear evid ence of spike events (i.e. high levels of silicone in older, buried se diments) which appear to be associated with major, documented storm ev ents on the island of Oahu, Silicone assay was by solvent extraction, and quantitative spectrophotometric measurement at 7.95 mu m The Ala W ai Canal is an anthropogenic hydrographic feature on Oahu. (C) 1997 by John Wiley & Sons, Ltd.