中国古人类遗址年代学问题

Chronological problems in Chinese human fossil sites

考古和年代学者们均已意识到在同一古人类遗址应用不同测年方法所得的年代可能存在较大差异,但长期以来该问题却一直未被系统阐述和研究.本研究对我国86处已发表古人类遗址的测年结果进行了统计和分析,尝试厘清这个问题.经统计发现U系测年法应用比例最大,在各测年方法中占有突出地位;37处遗址仅用了一种测年方法,28处使用了两种以上(包括两种)方法,不同方法测定同一遗址的年代结果存在差异,其中17处差异较大.同一遗址产生较大测年差异的原因可归纳为两大类:一类是遗址埋藏学问题,另一类是测年方法本身的差异.本研究提出针对不同时期遗址,采用不同方法组合的综合定年策略来解决测年差异问题,从而获得古人类遗址的准确年代,并建议应用该定年策略来重新评估我国一些重要古人类遗址的年代.

Archeologists and chronologists have realized that dating age divergence exists in some human fossil sites.However,this problem has not been systematically elaborated and studied to date.This paper makes statistics and analysis on the dating results of 86 published Chinese human fossil sites and attempts to clarify this problem.We find that the U-series dating method has the largest proportion of application and occupies a prominent position in each dating method,37 sites use one dating method,and 28 sites utilize more than two(including two)methods.Dating age divergence uses different methods in the same site,of which 17 sites are with large age divergence.We assume that the following are the reasons for the large dating age divergence in the same site:The taphonomy problems and the difference of the dating method itself.In summary,the problem of the dating age divergence in the same site is common.The taphonomy problems of human fossil sites must be discovered and corrected through multiple dating methods.The difference of the dating method itself also needs the combination of multiple dating methods for evaluation and judgment.We suggest the following multiple dating strategies:Early Pleistocene human fossil sites should mainly rely on paleomagnetic dating,and 26Al/10Be burial dating,climatic stratigraphy,and ESR dating methods should be combined to obtain a relatively accurate human fossil age.Middle Pleistocene sites should be based on paleomagnetic dating,climatic stratigraphy,26Al/10Be burial dating,U series,ESR/U series,TT-OSL,and pIRIR dating methods.Three or more dating methods must be selected for cross-examination.Late Pleistocene site dating must be performed on the basis of U series,14C,and OSL dating methods.14C dating and DNA analysis can be cautiously conducted in Late Pleistocene sites.The use of multiple dating methods can avoid accidental errors caused by only one dating method,especially in the cave sites of Middle and Late Pleistocene.The summary of the dating results for 86 Chinese human fossil sites shows that some sites have applied multiple dating methods.After cross-checking,the following sites obtained reliable ages:Yuanmou,Zhoukoudian Localities,Bailong Cave,Dali,Panxian Dadong,Jinniushan,Xujiayao,Tianyuan Cave,Shuidonggou,and Xiaogushan.Certain sites should be further checked by adding dating methods,such as,Yunxian,Hualongdong,Maba,Changyang,Hexian,Ganqian Cave,Xinglong Cave,Luna Cave,Huanglong Cave,Fuyan Cave,Wuguidong Cave,Xianren Cave,Tongzi Cave,Mao-Mao-dong Cave,Chuandong,and Maludong.Twenty-one sites,such as,Meipu Longgu Cave,Jimuyan Cave,Baojiyan Cave,Guoshandong Cave,and Zhuzailong Cave,still have no dating research.We must make a detailed investigation and reinvestigation because the fossil discovery records of these sites may be unclear,or they may have unsuitable dating materials.Obtaining some ages from these sites is significant.The accurate age of human fossil is the basis for establishing the correct theory of human evolution in China.Multiple dating strategies should be adopted for the newly discovered human fossil sites.Such strategies should be used to check and evaluate the age of some important Chinese human fossil sites that have been previously discovered.Doing so can further improve the reliability of the dating results for Chinese human fossil sites.