The Paleolithic site of Xibaimaying (XBMY), once considered the youngest flake tool site within the Nihewan Basin, North China, is an ideal archive to study the chronological relationship between flake tool and microblade industries in the Nihewan Basin during the Upper Palaeolithic, but the previous ages obtained for the site remain controversial. From 2015 to 2019, three areas at two archaeological localities (XBMY-I and XBMY-II) of the site were excavated, and well-preserved fossils and flake tools were unearthed. In this study, a total of 26 samples were collected from the three areas for optically stimulated luminescence (OSL) dating using a single-aliquot regenerative-dose (SAR) protocol on fine-grained quartz. A shared ‘Standardized growth curve’ (SGC) for a section was constructed to reduce the time required for D_e estimation. The long-term weighted average water contents of the samples during their burial period were estimated based on the in-situ water contents of continuous samples from a nearby borehole. All the OSL ages were modelled via Bayesian statistics using the OxCal software, modifying the OSL ages with stratigraphic constraints in each section. The results show that the cultural layer bearing flake tool assemblages falls within the period of 122–36 ka, indicating that the flake tool industry of the Xibaimaying site is comparable to that of the Youfangbei (108–86 ka), Banjingzi (∼86 ka) and Xinmiaozhuang (75–63 ka) sites, rather than the youngest one in the Nihewan basin, which explains why the Xibaimaying site is characterized as pure flake tool culture without any ‘advanced’ trait. The OSL dating results also shed new light on the study of sedimentary processes in the Xibaimaying site area. The different deposition rates (0.01–1.61 mm/a) for the sediments at the three newly excavated areas imply complex geomorphologic processes in the site area.

西白马营旧石器时代遗址（XBMY）曾被认为是华北泥河湾盆地最年轻的片状工具遗址，是研究泥河湾盆地旧石器时代晚期片状工具与微刀片工业年代关系的理想档案，但该网站之前获得的年龄仍然存在争议。2015年至2019年，对该遗址的两个考古地点（XBMY-I和XBMY-II）三个区域进行了发掘，出土了保存完好的化石和片状工具。在这项研究中，使用单等分再生剂量 (SAR) 协议对细粒石英进行光激发发光 (OSL) 测年，从三个区域共收集了 26 个样品。为一个部分构建了一个共享的“标准化生长曲线”(SGC)，以减少D所需的时间_e估计。根据附近钻孔中连续样品的原位含水量估算埋藏期间样品的长期加权平均含水量。所有 OSL 年龄均使用 OxCal 软件通过贝叶斯统计建模，在每个剖面中使用地层约束修改 OSL 年龄。结果表明，含片状工具组合的文化层位于122～36 ka时期，说明西白马营遗址的片状工具产业与油坊北（108～86 ka）、板井子（～86 ka）相当。 ）和新庙庄（75-63 ka）遗址，而不是泥河湾盆地最年轻的遗址，这解释了为什么西白马营遗址被描述为纯片状工具文化，没有任何“先进”特征。OSL测年结果也为西白马营遗址区沉积过程的研究提供了新的启示。三个新开挖区沉积物的不同沉积速率（0.01-1.61 mm/a）暗示了场地内复杂的地貌过程。