New U-series dates from Stump Cross Caverns, Yorkshire, UK, and constraints on the age of the Banwell Bone Cave Mammal Assemblage Zone

Stump Cross Caverns house one of the important Pleistocene fossil bone beds of the UK. Yet, the dates of the Banwell Bone Cave Mammal Assemblage Zone (MAZ), to which these belong, have not yet been well constrained. Here we present new U-Th dates showing that Late-MIS 5 bison-reindeer-wolverine fauna was present in northern England at least as early as 91.9 ± 0.5 ka (the oldest date yet published); and that the Banwell Bone Cave fauna probably occupied the Yorkshire Dales from soon after ∼100 ka to 80 ka (late MIS 5c-early MIS 5a). This adds to the very small number of dates for this fauna, is somewhat older than the timing proposed in the literature, and suggests that the fauna arrived in NW Britain more than 5 kyr in advance of SW Britain. We also found an older bone bed dating from 175 to 172 ka, MIS 6d. This is only the second reported occurrence in the Yorkshire Dales of a fauna that pre-dates the Last Interglacial. Our results confirm that calcite deposition in this cave is precluded during interglacial peaks by local flooding, but at other times is similar to other caves of NW Europe. The oldest dates, on calcites from the uppermost levels, show dewatering by at least ∼430 ka (early MIS 11), adding to our understanding of the antiquity of the caves and the geomorphology of the region.