摘要
古代瓷器、陶器、砖瓦和范土等文物的烧成温度区间不同,不同烧成温度的文物会对释光测年方法的适用性产生影响。本研究选择4种不同烧成温度的文物——上海青龙镇遗址出土的1件青釉瓷片、上海广富林遗址出土的1件陶片、山东龙山汉墓群出土的1件釉砖,以及三星堆出土的3件范土样品,使用多种释光测年方法进行测年。结果表明,对于陶瓷类文物的释光测年,可通过使用多种方法相互验证来提高测年结果准确度。基于最小损坏的取样原则,因少量样品无法有效地分离不同矿物,本研究对于每件陶瓷类文物样品采取混合矿物颗粒进行测年。结果表明:对于烧成温度较低(低于450℃)或烧成温度较高但烧成时间很短时的样品(如本研究中的范土样品,由于烧成温度太低,存在无法清空常规热释光法和前剂量法信号的问题,因此无法使用热释光法对范土样品准确定年),可使用钾长石pIR 50 IR 170信号单片再生(single-aliquot regenerative-dose,SAR)法进行测年;对于烧成温度介于约450~1150℃之间的样品(如本研究中的陶器和砖瓦样品),可针对其中的钾长石矿物使用常规热释光法和pIR 50 IR 170信号SAR法进行测年,而针对其中的石英矿物颗粒使用前剂量法测年——需注意的是前剂量法只适用于年代≤1500年的文物;对于烧成温度≥1150℃的样品(如本研究中的瓷器样品,由于其中的钾长石晶体大部分熔融成玻璃相无法使用常规热释光法和IRSL信号法测年),可针对样品内的石英矿物颗粒使用前剂量法和OSL信号SAR法测年。本研究初步证明光释光信号具有测定低温烧制文物年龄的潜力,具有更广泛的烧制温度适用范围。
The firing temperatures of ancient porcelain,pottery,bricks,tiles,and clay casing molds vary,and such variations can influence applicability of luminescence dating methods.In this study,four types of cultural relics with different firing temperatures were selected:a celadon porcelain shard unearthed from Qinglong Town Site,a pottery fragment unearthed from Guangfulin Site,a glazed brick unearthed from Longshan Tomb Group,and three clay casing molds for bronze wares unearthed from Sanxingdui Site.Multiple luminescence dating methods were applied to these samples.The results indicate that for luminescence dating of ceramic cultural relics,the accuracy of age could be improved through cross-validation using multiple techniques.Following the principle of minimal sampling damage,mixed mineral grains were used in dating analysis,as the limited amount of material made it difficult to effectively separate minerals.For luminescence dating of mixed mineral grains in ceramic relics,when the firing temperature is low(below about 450℃)or high but with a short firing duration,as in the case of the clay casing molds,conventional thermoluminescence(TL)and pre-dose methods fail to completely reset the luminescence signals during firing.In such cases,the pIR 50 IR 170 signal single-aliquot regenerative-dose(SAR)method can be used for dating.When the firing temperature is between about 450℃ and 1150℃,as in the case of the pottery and brick samples,conventional TL and pIR 50 IR 170 signal SAR methods are applicable to date K-feldspar minerals.For quartz mineral grains,the pre-dose method can be used for dating,though it is only applicable to cultural relics with the age≤1500 years.When the firing temperature is≥1150℃,as in the case of the porcelain sample,most K-feldspar crystals melt and vitrify,making conventional TL and pIR 50 IR 170 signal SAR methods unsuitable.The pre-dose and OSL signal SAR methods can be used for dating quartz grains.This study preliminarily demonstrates that the optically stimulated luminescence(OSL)method has potential for dating low-temperature fired cultural relics,and is applicable across a wider range of firing temperatures.
作者
杨宏宇
熊樱菲
赵晖
YANG Hongyu;XIONG Yingfei;ZHAO Hui(Shanghai Museum,Shanghai 200003,China;Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China)
出处
《文物保护与考古科学》
北大核心
2025年第6期50-59,共10页
Sciences of Conservation and Archaeology
基金
上海博物馆馆级青年项目(No.2023YB02)资助。
