Radiochemical dates obtained by alpha spectrometry on fossil mollusk shell from the 5e Atlantic shoreline of the High Atlas, Morocco

详细信息	查看全文 | 推荐本文 |

• 作者：A. Choukri ; O.-K. Hakam ; J.-L. Reyss ; J.-C. Plaziat
• 关键词：Th/U dating ; Sea level ; Mollusk shells ; Quaternary ; 5e interglacial substage ; High Atlas ; Morocco
• 刊名：Applied Radiation and Isotopes
• 出版年：2007
• 期刊代码：6_09698043
• 类别：ce
• 出版时间：August 2007
• 卷：65
• 期：8
• 页码：883-890
• 文件大小：181 K

摘要

The reported radiochemical results obtained on 77 samples collected from Moroccan fossil beaches assumed to be deposited during the above present sea-level high stands corresponding to 5e climatic stage, and on 12 present and Holocene samples, are discussed in order to judge the age validity. Contrary to the Holocene shells where ²³⁸U contents are low and ²³⁴U/²³⁸U are in agreement with sea–water ratio, the 5e results vary considerably irrespective of species and calcite content of samples. Because of the open-system possibility, the ²³⁰Th/²³⁴U ages based on shell samples should be interpreted as minima for any studied shoreline discussed in the light of geological data and several shells analyses.