沉积与特提斯地质2026，Vol.46Issue(1)：53-65,13.DOI:10.19826/j.cnki.1009-3850.2025.08011
川西雅砻江普巴绒段晚更新世早期河流阶地与相关沉积的发育特征、年代约束及其构造气候意义
Development characteristics,geochronological constraints and the tectonic-climatic significances of the Yalong River terraces and related sediments during early Late Pleistocene in Pubarong Town,western Sichuan
摘要
Abstract
In Yajiang County,western Sichuan Province,six levels of river terraces have developed along the mainstream area of the Yalong River in Pubarong Township,with red clay covering the terraces.Field investigations were conducted on the development characteristics of the river terraces and the overlying red clay.This study investigates the development characteristics of these terraces and the overlying red clay through field surveys,supplemented by optically stimulated luminescence(OSL)dating,pollen analysis,and grain size analysis.The aim is to discuss the climatic and environmental conditions during terrace formation and to determine the genesis of the overlying red clay.The evolution history of the Yalong River valley in the study area was clarified,with the main findings as follows:(1)The terraces in Pubarong Township are all pedestal terraces,standing 10-189 m above the river level.The T2 and T3 terraces formed during the last interglacial period,with ages of(87.7±4.1)ka and(101.5±4.8)ka,respectively,indicating a valley incision rate of approximately 2.03-2.42 m/kyr.The vegetation during the terrace formation was sparse grassland dominated by herbaceous plants.(2)The loess covering the terraces was deposited around(70.3±3.4)ka to(70.0±2.9)ka and represents wind-blown loess typical of the western Sichuan Plateau under a warm and humid climate.The loess material was derived from multiple sources,and locally,it has the characteristics of being transported and accumulated along slopes in the later stages.(3)During the laterization,vegetation shifted to forest-dominated communities.Climatic fluctuations during the last interglacial period were the key to triggering river incision and terrace formation.The transition from the last interglacial to glacial climate was an important factor in promoting loess deposition in the region.关键词
雅砻江/河流阶地/红色黏土/光释光测年/普巴绒乡Key words
river terrace/red clay/Yalong River/OSL dating/Pubarong Town分类
天文与地球科学引用本文复制引用
熊小辉,白永健,铁永波,高延超..川西雅砻江普巴绒段晚更新世早期河流阶地与相关沉积的发育特征、年代约束及其构造气候意义[J].沉积与特提斯地质,2026,46(1):53-65,13.基金项目
四川省自然科学基金(2023NSFSC0286) （2023NSFSC0286）
四川省自然资源厅科研项目(KJ-2023-012) （KJ-2023-012）
中国地质调查局地质调查项目(DD202606100904) （DD202606100904）
