Abstract
This study focused on the lumines- cence dating of sediments from Lake El'gygytgyn, a meteorite impact crater 100 km north of the Arctic Circle in northeast Siberia, formed 3.58 Ma ago. The sediment is principally eolian deposited in to a lake with nearly permanently ice. The fine-grained polymineral and quartz extracts taken from nine distinct levels from the upper 12.3 m of sediment core PG1351 were dated by infrared stimulated (IRSL) and green stimulated luminescence (GSL) using multiple aliquot additive dose procedures. The veracity of these ages is evaluated by comparing to an age model for the core derived from magnetic excursions and from correlation of variations of the magnetic susceptibility record to similar magnitude variations in d 18 O in the Greenland Ice core record. The IRSL ages from the upper 9 m of core correspond well with the independent age control for the past ca. 200 ka. However, sediments deeper in the core at 12.3 m with an inferred age of ca. 250 ka age yield a saturated IRSL response and therefore a non-finite OSL age. The youngest sediment dated from 0.70 m depth yielded the IRSL age of ca. 11.5 ka, older than the corresponding age of 9.3-8.8 ka, indi- cating a discrepancy in dating the youngest sedi- ments in the upper 1 m of core. This study confirms the utility of IRSL by the multiple aliquot additive dose method to date sediments < 200 ka old from eastern Siberia.
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