Isochron dating of sand-loess-soil deposits from the Mu Us Desert margin, central China

A sand-loess-soil sequence from the margin of the Mu Us Desert was studied using the isochron infrared stimulated luminescence (IRSL) dating method utilizing K-feldspar grains extracted from sediments. Although the IRSL ages measured with the conventional method showed underestimation as a result of anomalous fading, the isochron results are broadly consistent with independent ages based on stratigraphic correlation in a glacial/interglacial scale over the last 250 ka. For samples older than 250 ka, the IRSL signals approached in field saturation and the isochron dating gave ambiguous results, suggesting an age limit for the method.

► A sand-loess-soil sequence was studied using the isochron IRSL dating method utilizing K-feldspar grains.
► The isochron results provide an absolute chronology framework for the sequence over the last 250 ka.
► For samples older than 250 ka, the IRSL signals approached in field saturation and reach a dating limit.