Layer 1 has been dated as beginning around 3800 BP, and consists of loose aeolian sand at the very top, slightly cemented sand and dung below that, and hearths at the bottom. Further down, layer 2 has evidence of humified organic sand and lenses of fresh plant remains. These two layers represent the period of human occupation of the shelter. Layer 3 has even stronger humidified sand, as well as gypsum concretions. The stratigraphic sequence suggests that the shelter was inhabited during a much wetter period than today.