Abstract: Between 2010 and 2012, Nine Paleolithic open-air sites were identified and 211 stone artifacts were collected in the Shangdan Basin (Shangluo-Danfeng Basin) in the eastern Qinling Mountains, central China. These newly discovered sites are distributed on the third terrace of the upper Danjiang River valley. The in situ lithic artifacts buried in the aeolian silt loess deposits with loess and paleosol alternations at the third terrace in the sites. Based on the analysis of loess stratigraphy, the age of buried lithic artifacts layer is no earlier than 780ka BP, it spans approximately from 780ka to 200ka BP.
The lithic assemblage analysis suggests that the stone artifacts were made of local raw materials which came from the pebbles/cobbles of the Danjiang River. They were procured, transported, and used by early hominines at these locations. Hominines selected a variety of raw materials for tool manufacture, however the preference was given to isotropic pebbles/cobbles such as quartz, quartzite, and greywacke. Sandstone, igneous rock, and silicon limestone were infrequently used for tool manufacture. The main percussion techniques that were used are direct hard hammer percussion? and ?bi-polar? techniques.? The ?core ?and ?flake ?platforms ?are? dominated? by ?cortical? surfaces.? The ?stone ?artifacts? consist ?of ?hammer? stones,? cores, ?flakes,? retouched ?tools? and? flaking ?debris.? Tools? include a variety of Mode I “chopper-chopping tools” such as choppers, spheroids and scrapers, In addition,? Mode ?II ?Acheulian-like ?stone? artifacts ?such? as ?hand-axes? and ?picks ?were ?identified? as? well.? The lithic artifacts morphology and tool composition in these open-air sites of the Shangdan Basin share some common features with the open-air sites in South China, such as the Luonan Basin in Shaanxi Province, and the Bose Basin in Guangxi Zhuang Autonomous Region. It represents Acheulian-like lithic industry with presence of retouched heavy-duty and light-duty tools.

Key words: Danjiang River; Shangdan Basin; Loess; Open-air site; Paleolithic