A radical reassessment of the stratigraphy, palaeoenvironmental processes and dating of the Middle Pleistocene deposits at Schöningen, northern Germany

Open-cast lignite mining east of the town of Schöningen revealed in the North Pit and the South Pit a unique sequence of late Middle Pleistocene deposits. In the North Pit, we recognised a series of alluvial fan deposits, overlying Elsterian glacial sediments, and originating from the Muschelkalk massif of the Elm during the Elsterian late-glacial. Channels and basins eroded into the alluvial fans filled with Holsteinian Interglacial sediments. At the end of later cold stages, periglacial meltwater from these channels temporarily avulsed, eroding two deep, major north-south-oriented channels: the Reinsdorf Interglacial Channel (Channel II) and the Schöningen Interglacial Channel (Channel III), which developed into lakes along the valley floor. The Reinsdorf Channel consists of a sequence of narrow, superimposed subchannels, again eroded by floodwaters, primarily containing beds of silt, detrital mud, and peat deposits, which represent five, sometimes six, sedimentary cycles that can be traced along the entire length of Channel II. The combined stratigraphical data from the North and South Pits reveal three successive interglacials, each with a distinct vegetation succession. These are located between the Elsterian glacial deposits at the base of the Schöningen sequence and the Saalian till found higher up; the Holsteinian Interglacial, the Reinsdorf Interglacial, and the Schöningen Interglacial, which correspond with Marine Isotope Stage/Substage (MIS) 11c, MIS 9e, and MIS 7e, respectively. The mammalian biostratigraphical data support the MIS 9 age of the Reinsdorf Interglacial deposits and indicate an age of ca. 300 ka for the Schöningen wooden spears.