第四纪沉积物常用测年方法及其适用性研究

由于沉积环境与成因的不同，第四纪地层的岩性、成分、结构和厚度在短尺度空间范围内可能发生明显的变化，地表松散沉积物在自然营力的作用下容易受到剥蚀、搬运和再沉积；在气候变化、生物活动、特别是水的作用下，其化学成分和结构也会发生变化，因此，第四纪地层不仅在空间上复杂多变，而且其组成、岩性等也随时间变化。本文讨论了第四纪松散沉积物的测年问题，对各种测年方法适用的测定对象与测年范围作了分析和对比，力求获得最接近于地层沉积年龄或地质事件发生年龄的数据。

DATING METHODS USED IN QUATERNARY NONCOHESIVE SEDMENTS AND THEIR USABILITY

Quaternary stratum may have obvious changes of short-term temporal scale in lithostratigraphy, composition and thickness because of different sedimentary conditions and forming causes. The non-cohesive sediments on the earth's surface are ready to undergo erosion, transposition and re-sedimentation under the operation of the natural forces. Changes in the Quaternary sediments in chemical compositions and structures also come because of the affection of the climate variation, biotic activities, and especially the existence of water. The Quaternary sediments, therefore, changes in spatial aspect and their compositions and lithostratigraphic features also have variation with changing time. This paper discussed the dating problems for Quaternary non-cohesive sediments, various dating methods and their usability for dating materials and also the dating ranges are analyzed and compared with the aim to obtain the ages data which is as close as possible to the real time when the strata and the geo-events occur.