In the ‘Winterswijksche Steen- en Kalkgroeve’, situated in the eastern Netherlands, Lower Muschelkalk limestones are quarried. A ca. 30 m wide area in the quarry face showing fragmented rock material in chaotic accumulation in between stratified Muschelkalk sediments was interpreted until now to be the result of karstification or tectonic fragmentation. The present investigation indicates that it originated as a subrosion pipe fill that formed by continuous upsection collapse which commenced in the Röt gypsum and anhydrite beds more than 200 m below. The pipe fill is dated probably to one of the Quarternary interstadials when these rocks were dissolved by groundwater at even greater depths.
