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Tylmann, W. Include files Advanced Search Browse. View item. Calibrating Pb dating results with varve chronology and independent chronostratigraphic markers: problems and implications Tylmann, W. Genre : Journal Article. Files show Files.

14C sediment dating , Pb, sediment mixing, Th excess sediment dating . Introduction. Over several decades, low- and medium-activity-level radioactive.

Lead, Cs and Am dating techniques have been extensively used in the dating of recent sediments. However, collection of an intact core is the first essential step towards having reliable Pb chronologies for the sediments. We collected short gravity cores from Loch Morar, a deep m max. Lead chronologies for one of the cores did not match with the Cs and Am records, and the radionuclide data indicate that surface sediments in this core were likely missing.

Therefore, sediment chronologies and accumulation rates calculated from unsupported Pb activities in the core were deemed unreliable, as confirmed by another core from the same lake. Dating of the cores suggests that sediment dating not only depends on accurate counting of radionuclide activities, but also on the integrity of the cores, in turn determined by sampling location.

Importantly, however Pb, Cs and Am data can be carefully assessed to determine the integrity of sediment cores. UCL Discovery. Enter your search terms. Downloads since deposit. Download activity – last month. Download activity – last 12 months.