@ARTICLE{Gąsiorowski_Michał_Lacustrine_2001, author={Gąsiorowski, Michał}, volume={Vol. 18}, journal={Studia Quaternaria}, pages={17-24}, howpublished={online}, year={2001}, publisher={Committee for Quaternary Research PAS}, publisher={Institute of Geological Sciences PAS}, abstract={Lacustrine chalk is very common in post-glacial lakes of northern Poland. In the deposit of Lake Kruk lin (NE Poland) carbonates occur as a layer 2-3 m thick. Samples for laboratory studies were collected from three profiles in SW part of the deposit. Mineral composition of the sediments was determined using differential thermal analysis (DT A) and thermogravimetry analysis (TGA), while the age was determined on the basis of pollen analysis. The sediment profiles represent an age of early Holocene. Calcite is the major component of lacustrine chalk. It forms small crystals (