Инд. авторы: | Agatova A., Nepop R., Zazovskaya E., Ovchinnikov I., Moska P. |
Заглавие: | Problems of Developing the Pleistocene Radiocarbon Chronology within high Mountain Terranes by the Example of Russian Altai |
Библ. ссылка: | Agatova A., Nepop R., Zazovskaya E., Ovchinnikov I., Moska P. Problems of Developing the Pleistocene Radiocarbon Chronology within high Mountain Terranes by the Example of Russian Altai // Radiocarbon. - 2019. - P.2019-2028. - ISSN 0033-8222. - EISSN 1945-5755. |
Внешние системы: | DOI: 10.1017/RDC.2019.83; SCOPUS: 2-s2.0-85075203793; WoS: 000504752800037; |
Реферат: | eng: The paper presents a discussion of 24 radiocarbon (14C) dates of organic material from deposits of various genesis within the intermountain depressions and valleys of the Russian Altai. These apparent 14C ages (sometimes near the upper time limit of the 14C dating method) contradict to other proxy data and optically stimulated luminescence (OSL) dates. Rejuvenation of ancient deposits by 14C dating encountered two problems: (1) wrong interpretation of previously unknown near-surface location of Tertiary deposits as being of the Pleistocene ones with the redeposited ancient flora; and (2) wrong age estimation of the Pleistocene-Holocene deposits with redeposited Carboniferous, Jurassic, and Neogene organic material, which is represented as inclusions. Significant scattering of 14C ages, their inversion within a section, and discrepancy with other proxy data indicate penetrating of the 'young' carbon into ancient organic material, and its presence in a unique (for each sample) ratio. Today such contamination cannot be eliminated utilizing standard pre-treatment techniques. The influx of 'young' carbon is related to post-sedimentation tectonic and exogenous processes, which are common for tectonically active mountain provinces including Altai. The reported problem is not a new one, although methodological studies in the Russian Altai have not yet been carried out earlier. © 2019 by the Arizona Board of Regents on behalf of the University of Arizona.
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Ключевые слова: | Russian Altai; radiocarbon dating; paleogeographical reconstructions; apparent 14C ages; |
Издано: | 2019 |
Физ. характеристика: | с.2019-2028 |