A large ice‐dammed lake in the western Danish North Sea: Deglacial evolution and ice‐margin dynamics

Abstract The Last Glacial Maximum (LGM) ice extent in the western Danish North Sea remains unchartered, which impedes our understanding of the last glacial to Holocene transition in the region. Despite increasing interest in the shallow subsurface of the North Sea, there is still a knowledge gap concerning this transition. In this study, we describe the geological evolution of the southern part of the western Danish North Sea using high‐resolution seismic data, with emphasis on the LGM and the late Quaternary development. We have identified a large glaciotectonic complex that delineates the maximum extent of the LGM ice sheet and indicates a general NNW‐SSE ice flow direction. We describe the drainage history associated with a large ice‐dammed lake, which covered most of the southern North Sea, presumably lasting for more than 2000 years from the LGM until ~19 cal kyrs BP. Based on the interpreted seismic profiles and regional depositional and deformational patterns, we provide a model for how the deglaciation unfolded in the western Danish North Sea. The deglacial sequence of events is placed into a late Quaternary context and related to the existing stratigraphic models for the area. Our study sheds new light on the distribution of potentially challenging buried landscapes for offshore construction and windfarm development.