Effect of Glacier-permafrost on Isotopic Formation and Sampling Method of 14~C Dating
Gu Gongshu, Chen Huiqin and Zhang Hongwei (Lanzhou Institute of Glaciology and Geocryology, Chinese Academy of Scienses)
The reliability of 14C dating data is relatively reduced by the buried environment alternations, characteristics and late polluted extent of the samples obtainned from glacial and permafrost areas. The rehcts of logs and twigs reminded in glaciers and lacustrine silt show more reliability for 14C dating than that in permafrost soil. Additionally, the C-isotopic formational mechenism in sedimentory procpess and the comparison between the inorganic 14C dating and organic 14C dating show that the late pollusion results in various negative deviations and various inferences of old carbon to the 14C dating, so that it is hard to get perfect data from the inorganic 14C dating. However,because of the existing of C-isotopes in the balanced primary sedimentory environment, the inorganic 14C dating data can only be referenced. It is proposed that the dissolving and illuviational quantitative models of inorganic carbon in soil should be futher studied from now on, so as to use the 14C dating data precisely. In addition, in order to make the 14C dating data reflect its real dates, sampling methods should be identified and typical samples should be obtained normally.