What is Luminescence? Optically Stimulated Luminescence (OSL) Sediment Context Collection Procedures

Luminescence geochronology for sediments

Lake El'gygytgyn, northwest Siberia, Russia

Constraining the timing of paleoenvironmental events for the past 200 ka.


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This study focused on the luminescence 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 fine-grained polymineral and quartz extracts taken from nine distinct levels from the upper 12.3 m of sediment core PG1351 are dated by infrared stimulated (IRSL) and green stimulated luminescence (GSL). The veracity 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 18O 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 corresponding to ca. 290 ka age, yielded a 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 correlative age of 9.3-8.8 ka, indicating a discrepancy in dating the youngest sediments in the upper 1 m of core.
S. L. Forman, J. Pierson, J. Gomez, J. Brigham-Grette (UMASS-Amherst), N.R. Nowaczyk (GeoForschungsZentrum Potsdam, Germany) and Martin Melles (University of Leipzig, Germany)