A study of the relative and absolute chronology of the Middle and Late Yayoi period

本研究的目的如下：a)检查不同类型的测年材料，特别是附着在罐子表面的煤烟、烧焦的种子和人骨上的煤烟，在AMS测年结果中可能引起的差异的性质；以及b)比较不同类型测年材料的AMS测年结果与由TPQ确定的弥生中晚期的一些绝对日期(即，从亚洲大陆和朝鲜半岛进口的绝对可确定年代的文物（如汉代铜镜）。值得注意的结果如下：1)通过检查从这两个地区出土的相同类型的壶，对各个年代阶段之间的同时代性进行严格的交叉检查，九州北部和濑户-关西地区的相对年代阶段大致是同步的。除了从中期到晚期弥生的过渡阶段，濑户-关西地区晚期弥生时期的第一阶段开始于九州北部地区晚期弥生时期的前半段的后半段。2)九州北部地区晚矢生人上半期下半期埋罐出土器物的TPQ测定时间为公元50~ 75年；这对广泛接受的濑户-关西地区晚弥生时代开始于公元1年左右的日期的有效性提出了一个严重的问题。3)对烧焦种子的AMS测年结果显示的日期比从亚洲大陆进口的人工制品的TPQ测定的日期要早得多。如上所述，九州北部地区晚期弥生时代前半部分的后半部分的日期为公元50年~公元75年，而从烧焦的种子中获得的日期约为公元1年。这使得进一步研究不同测年材料可能造成的差异是绝对必要的。

The objectives of this research were as follows:a) to examine the nature ofpossible dating material-caused discrepancies in the outcomes of the AMS dating of different types of dating materials, particularly soot adhering to the surface of pots, charred seeds and human bones;andb) to compare the outcomes of the AMS dating of different types of dating materials with some absolute dates of the Middle and Late Yayoi periods determined by the TPQ (i. e., Terminus Post Quem) of imported absolute-datable artifacts (e. g. Han Bronze mirrors) from Mainland Asia and the Korean peninsulaThe notable outcomes are as follows:1) From a rigorous cross-checking of contemporaneity between individual chronological stages by examining same types of pots excavated from the both regions, the relative chronological stages of the northern Kyushu and Setouchi-Kansai regions are roughly contemporaneous stage by stage, except the transitional stages from the Middle to the Late Yayoi where the first stage of the Late Yayoi period of the Setouchi-Kansai region began sometime during the later half of the first half of the Late Yayoi of the northern Kyushu region.2) The TPQ of the artifacts excavated from burial jars dated to the second half of the first half of the Late Yayoi of the northern Kyushu region has been determined to date from AD 50~AD 75, and this poses a serious question to the validity of the widely accepted date for the beginning of the Late Yayoi of the Setouchi-Kansai region to be around 1 AD.3) The outcomes of the AMS dating of charred seeds show considerably earlier dates than what are determined from the TPQ of the imported artifacts from Mainland Asia. The date of the second half of the first half of the Late Yayoi of the northern Kyushu region, as mentioned, dates from AD 50~AD 75, whereas the dates obtained from the charred seeds are around 1AD. This makes further researches into possible discrepancies caused by different dating materials of absolute necessity.