Pleistocene
Charcoal layer marking a fire on the steppe in the Ice Age

The dry and warm weather always enhances the hazard of spontaneous combustion. At the end of the Ice Age, steppe and forest-steppe vegetation developed repeatedly in the Carpathian Basin. This type of vegetation was recurrently renewed by wasting fires. The charcoal product of the fires was usually removed from the surface by wind and rain, but sometimes it remained in situ and forms a well-recognizable layer.