晚更新世以来贵州清水江阶地发育及地貌意义  

The Development of Terraces and the Implications for the Geomorphologic Evolution of the Qingshuijiang River in Guizhou Plateau Since the Late Pleistocene

作　　者：樊云龙 王懿萱[2] 罗光杰 任大银 李宗盟 刘芬良 罗绪强 唐亮 白庆玲 黎成都 Fan Yunlong;Wang Yixuan;Luo Guangjie;Ren Dayin;Li Zongmeng;Liu Fenliang;Luo Xuqiang;Tang Liang;Bai Qingling;Li Chengdu(Guizhou Provincial Key Laboratory of Geographic State Monitoring of Watershed,School of Geography and Resource Science,Guizhou Education University,Guiyang,550018,Guizhou,China;Qinghai Institute of Salt Lakes,Chinese Academy of Sciences,Xining 810008,Qinghai,China;School of Geographic Sciences,Xinyang Normal University,Xinyang 464000,Henan,China;Department of Geographic Information System Science,Hunan City University,Yiyang 413000,Hunan,China)

机构地区：[1]贵州师范学院地理与资源学院贵州省流域地理国情监测重点实验室,贵州贵阳550018 [2]中国科学院青海盐湖研究所,青海西宁810008 [3]信阳师范学院地理科学学院,河南信阳464000 [4]湖南城市学院地理信息科学系,湖南益阳413000

出　　处：《地理科学》2022年第9期1676-1684,共9页Scientia Geographica Sinica

基　　金：国家自然科学基金项目(42061001,41501006);贵州省科技计划基础研究项目(黔科合基础-ZK[2021]一般190);贵州省教育厅自然科学研究项目(黔教合KY字[2021]036)资助。

摘　　要：对贵州清水江上游马寨、翁东、三江、施洞沿江4个剖面的阶地特征、年代学结果进行了综合分析。发现以凯里断层为界,上游地区的马寨和翁东2个剖面的T2阶地形成时代约为51~57 ka B.P.,T1阶地的形成时代约为25 ka B.P.,下游地区的三江和施洞2个剖面的T2阶地形成时代约为122~102 ka B.P.,T1阶地的形成时代约为78 ka B.P.。选取各剖面的T2阶地的基座高度来计算了河流下切速率,发现上游地区2个剖面(马寨、翁东)的河流下切速率较接近,约为0.41~0.34 m/ka,明显高于下游地区的2个剖面(三江、施洞)的0.16~0.20 m/ka,表现为上游下切速率高,越往下游方向下切速率逐渐降低。这表明自晚更新世以来,清水江上游区域受到构造作用的影响而发生差异抬升,具体表现为西部构造抬升幅度大,阶地下切速率快;东部构造抬升幅度小,阶地下切速率慢。River terraces can act as a geomorphic record of tectonic uplift and have been used to characterize regional geomorphologic evolution.The terrain of the Guizhou Plateau has gradually developed a pattern of higher and lower elevation in the west and east,respectively since the Cenozoic.River terraces have shown positive and sensitive responses to this process.The Qingshuijiang River in eastern Guizhou is a tributary of the Yuanjiang River.A two-strath terrace has generally formed on both banks of the Qingshuijiang River,characterized by well-preserved fluvial facies.This study comprehensively analyzed the formation ages of the terrace morphology of four sections along the river.The results showed that the formation age of the T2 terrace in the Mazhai and Wengdong sections in the upstream area is 51-57 ka B.P.,whereas that of the T1 terrace is 25 ka B.P.The formation age of the T2 terrace of the Sanjiang and Shidong sections in the downstream area is 122-102 ka B.P.,whereas that of the T1 terrace is 78 ka B.P.The bedrock height of the T2 terrace of each profile was selected to calculate the river incision rate.The results showed similar river incision rates between the two profiles in the upstream area(Mazhai and Wengdong)of 0.41-0.34 m/ka respectively,significantly higher than that of the two profiles in the downstream area(Sanjiang and Shidong).This result indicated a higher incision rate upstream,with the incision rate gradually decreasing downstream.The upper reaches of the Qingshuijiang River have experienced differential uplift under the influence of tectonism since the Late Pleistocene.This process was characterized by a large tectonic uplift in the west and a rapid incision rate,whereas the opposite pattern occurred in the east.

关 键 词：阶地 下切速率 清水江 贵州 

分 类 号：P931.1[天文地球—自然地理学]