丹江上游商丹盆地新发现的旧石器及其埋藏黄土地层

2010~2012年在东秦岭丹江上游商丹盆地(商洛-丹凤盆地)第三级阶地顶部黄土堆积地层中新发现9处旷野旧石器地点, 采集石制品211件, 部分石制品直接采自遗址黄土地层剖面上。加工石制品的原料来自于丹江河床的石英质砾石, 其次是石英岩和石英砂岩砾石, 砂岩、火山岩和硅质灰岩等砾石原料偶尔被使用。早期人类主要采取锤击法直接剥片, 砸击法剥片技术也被使用, 碰砧法剥片可能只是在偶尔的情况下才被采用。石核和石片以自然砾石台面者居多。石制品种类有石锤、石核、石片、工具和断块及碎片屑。工具中砍砸器数量最多, 其次是大型石片为毛坯加工而成的重型刮削器与小型刮削器, 石器中还有一定数量的石球、手斧和手镐, 商丹盆地的石制品可视为含阿舍利(Acheulian)器物组合类型的石器工业。根据遗址的黄土-古土壤地层序列, 初步判断商丹盆地丹江第三级阶地旧石器地点埋藏石制品的黄土-古土壤地层时代为中更新世中晚期, 在获得地层绝对测年结果之前, 石制品年代可暂置于旧石器时代早期偏晚阶段。

New discovered Paleolithic open-air sites at Shangdan Basin in the upper Danjiang River Valley,eastern Qinling Mountains,central China

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.