Varve chronology of core GOS18 from Lake Gościąż

To revise the chronology for the Lake Gościąż record, sediment cores were retrieved during two field campaigns in 2015 and 2018. Four overlapping sections were collected using a UWITEC Piston Corer (Ø 90 mm) in the deepest part of Lake Gościąż, Poland (52.583022 N, 19.339946 E). The chronology was obtained by triple varve counting on petrographic thin sections that was complemented by 137Cs measurements and 14C AMS dating of terrestrial plant remains. Additionally, part of the chronology between 520-758 cm was obtained through age-depth modelling. Pollen analysis was performed for seventy one samples, prepared according to standard procedure, and analyzed in three intervals: i) from 1859.9 cm to 1874.4 cm with 2 cm resolution, ii) from 1880.2 cm to 1896.7 cm with 1-2 cm resolution and iii) from 1741.4 cm to 1798.4 cm with 0.5-3 cm resolution. The record is mostly varved and the bottom of the composite profile coincides with the onset of lacustrine sedimentation in the late Allerød at 12,834 +134/-233 varve yrs BP.