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These Mauer sands, including sands and gravels, were deposited by the Neckar River in its former course and are subdivided into two distinct units: the “lower sands” and the “upper sands,” separated from each other by a clay/silt layer, the “Lettenbank” (Fig. The mandible of Both sand units are renowned for their rich early Middle Pleistocene mammal fauna that clearly indicate warm climate conditions (2) attributed to two distinct Middle Pleistocene interglacial stages.
The good preservation of the mammal bones (2)—and in particular of the human mandible—indicates that they were transported from a nearby fluvial floodplain before becoming embedded in the river deposits (i.e., they have the same geological age as their surrounding sediment layers).
We have calculated 108 dates (10–20 per dated layer) and can minimize errors caused by incomplete reset of the luminescence clock—resulting in age overestimation—due to insufficient light exposure in the fluvial sediment environment (7, 8).
Ages of 607 ± 55 ka, 603 ± 56 ka, 554 ± 33 ka, and 502 ± 27 ka were obtained for the lower sands, whereas the upper sands gave ages of 508 ± 50 ka and 420 ± 23 ka (Fig. Eight herbivore teeth (five from the lower sands and three from the upper sands) were analyzed with the ESR-US technique (9).
A minimum age for the SH deposits is now reported to be 530 ka (19), whereas specimens from the British, French, and Italian localities are dated at 500 ka or younger.
Taking into account that the find layer was deposited in an interglacial stage, the bracketing data of M0503 and Mau 3 give additional support to this correlation (i.e., it is confirmed by a set of five dates).Age estimates for the Mauer mandible have been advanced previously.The Mauer sands are overlain by several Middle and Late Pleistocene glacial loess layers with interstratified interglacial paleosoil horizons, which constrain the age of the fossil to older than 350 ka (3).Mammalian biostratigraphy places the find layer in a young, but not the youngest, interglacial of the Cromerian complex, probably Cromerian IV or Cromerian III (2, 4).The faunal assemblage from the lower sands, including at Mauer matches or may be slightly less advanced than that at Isernia, indicating that Mauer should be at least as old as the Italian locality (4).