摘要
以代县选仁村古文化遗址剖面为层型，在前人工作的基础上，将河流Ⅰ级阶地堆积建立选仁组。该组二元结构清晰，地貌特征明显，有同位素测年数据，与下伏峙峪组为侵蚀不整合接触。据地貌单元和测年资料，该组时限１２０００—２３００ａ，为全新世早期。将高河漫滩阶地和现代河床堆积建立沱阳组，属河流最新堆积，地貌特征明显，系明显切割选仁组（Ⅰ级阶地）地层之后再堆积而成，其下限年龄２３００ａ，为全新世晚期地层。
On the basis of previous work ,the Xuanren Formation consisting of river terrace Ⅰ deposits has been established with the section of ancient cultural remains at Xuanren Village ,Daixian,as the stratotype.This formation has a distinct binary structure and pronounced geomorphological features as well as isotope age data.It is in erosional unconformable contact with the underlying Zhiyu Formation.In light of geomorphological units and age data,the age range of the formation is 12000 2300 a ,assigned to early Holocene.The Tuoyang Formation has also been set up .It consists of the high floodplain terrace deposits and modern channel deposits ,belonging to the youngest fluvial deposits .It has prominent geomorphological features and is considered to be formed by redeposition after dissecting the Xuanren Formation (Ⅰ terrace deposits).Its lower limit age is 2300 a ,pertaining to late Holocene.
出处
《中国区域地质》
CSCD
1996年第3期228-231,共4页
Regional Geology of China
