期刊
ANAIS DA ACADEMIA BRASILEIRA DE CIENCIAS
卷 82, 期 3, 页码 691-699出版社
ACAD BRASILEIRA DE CIENCIAS
DOI: 10.1590/S0001-37652010000300017
关键词
crystal luminescence dating; Quaternary; fluvial terraces; Central Amazonia
资金
- Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES-PQI) [00044/03-2]
Absolute dating methods have been used in chronological studies of geological processes and sedimentary units of Quaternary age in Central Amazonia, Brazil. Although radiocarbon dating has been very useful in archaeological research and soil studies, the temporal interval of this method is inefficient in evaluating the sedimentation aspects and geological events from the beginning of the Quaternary in the Amazon basin. The use of crystal luminescence dating has been one of the most promising tool for determining the absolute dating of Quaternary deposits in the Amazonian region. Optically stimulated luminescence (OSL) dating, following the MAR and SAR protocols, in a tectonic-sedimentary study of Quaternary fluvial deposits in the confluence area of the Negro and Solimoes rivers, indicated ages from 1.3 (Holocene) to about 67.4 kyears (Late Pleistocene) for these sediments. Low radioactive isotope concentrations were found about 2ppm for U-235 and U-238; 5ppm for Th-232; and the K-40 concentrations were almost zero. A comparison was made between MAR and SAR protocols taking into account the fluvial depositional process.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据