3D sedimentary architecture of sandy interbeds within massive lacustrine deposits – Lednica Lake, Poland

The article presents an integrated reconstruction of sediment development and lake-floor morphology in the western part of Lednica Lake, an archaeological site in Poland, based on instrumental datasets, underwater investigations, and core analyses. Its main outcome is a 3D (4D) map and model synthesising bedforms, depositional-unit boundaries, and spatial relations between the inflow zone and the area of deposition. The results show that the sand wedge at the stream outlet is natural and linked to episodic high-energy events rather than human activity. Combining spatial information with archival data and field observations allows reconstruction of the processes responsible for sandy deposition at the mouth of a former bay within a late-Holocene framework. The workflow, integrating lake-floor imaging, ground-truthing, and hydrodynamic verification, is transparent and reproducible. The main map provides a reference for studies of Lednica Lake and a transferable template for identifying episodic sandy deposits in other massive, weakly laminated lake systems.