Stratigraphical and palaeontological data from the Early Pleistocene Pirro 10 site of Pirro Nord (Puglia, south eastern Italy)

Pirro 10, Pirro 13 and all karst structures of the Pirro Nord locality during Early Pleistocene were part of a complex interconnected karst system. Dissolution was more effective along the highly fractured core-zones of the Pliocene fault that bounded the “Apricena horst” to the south, where Pirro 10 gallery and Pirro 13 shaft are located. At that time, Pirro 10 was developed within the vadose zone whereas Pirro 13 represented a vertical structure connecting the surface to an underground karst floor. In general, the filling of Pirro 10 indicates fluctuations of the base level: water flow circulation in phreatic and epiphreatic conditions led to the deposition of clastic sediments, whereas flowstones reflect base level lowerings.