Sandy beach ridges from Xingkai Lake (NE Asia): Timing and response to palaeoclimate

Lake beach ridges and their sediments have been investigated as palaeoenvironmental records. Robust chronology is crucial to utilize this archive for palaeoenvironmental reconstruction and interpretation. This study investigates the optically stimulated luminescence (OSL) dating of quartz in two beach ridges of aeolian origin from Xingkai Lake (NE Asia). The applicability of the selected measurement procedure is validated by a set of internal tests on luminescence characteristics such as preheat plateau test and dose recovery test, and the reliability of the resulting 24 OSL ages are also confirmed by agreement with four 14C ages as well as two K-feldspar luminescence dates. The constructed chronologies are thought to be robust in the stratigraphic and geomorphologic context. The two aeolian beach ridges (B1 and B2) are dated to ∼32-15 ka and ∼1.2-0.5 ka, respectively, which are interpreted as two distinct periods of lake lowstand that could have caused beach exposure and provided a more extended sand source for foredune formation around Xingkai Lake. These two lowstands could be correlated to the dry/cold regional climate including the time span from late MIS3 to late glacial and the most recent one at the late Holocene.