| http://www.w3.org/ns/prov#value | - In some caves, particularly sandstone caves such as Petzkes Cave, sediment may only accumulate at a rate of a few centimetres per century; materials near the surface are subjected to the combined trampling disturbance of all the occupations occurring in that time-span (Hughes & Lainpert 1977; 136; Villa & Courtin 1983: 270).
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