地理学报 ›› 2006, Vol. 61 ›› Issue (3): 249-254.doi: 10.11821/xb200603003

• 地貌 • 上一篇    下一篇

川西高原杂谷脑河阶地的形成

刘勇, 赵志军, 李才林, 张茂恒, 陈晔   

  1. 江苏省环境演变与生态建设重点实验室;南京师范大学地理科学学院,南京 210097
  • 收稿日期:2005-09-19 修回日期:2005-12-05 出版日期:2006-03-25 发布日期:2006-03-25
  • 作者简介:刘勇 (1981-), 男, 湖北枣阳人, 硕士研究生, 主要从事地貌与第四纪环境演变研究。E-mail: lzu414@163.com
  • 基金资助:

    国家自然科学基金项目 (40201007)

Formation of the Zagunao River Terraces in Western Sichuan Plateau, China

LIU Yong, ZHAO Zhijun, LI Cailin, ZHANG Maoheng, CHEN Ye   

  1. Jiangsu Key Laboratory of Environmental Change and Ecological Construction; College of Geography, Nanjing Normal University, Nanjing 210097, China
  • Received:2005-09-19 Revised:2005-12-05 Online:2006-03-25 Published:2006-03-25
  • Supported by:

    National Natural Science Foundation of China, No.40201007

摘要:

根据野外实地地貌调查,确定了川西高原杂谷脑河理县段发育了8级阶地,并对阶地沉积物进行了ESR年代测试,初步确定杂谷脑河第II,III,IV,VI级阶地约形成于距今54,125,248,481ka。阶地成因分析表明这些主要阶地序列主要是构造隆升的结果,因此,杂谷脑河各级主要阶地分别代表了川西高原中更新世以来的几次隆升事件。根据阶地高程和阶地形成年代确定的杂谷脑河下蚀速率为0.39m/ka,与大地测量获得的龙门山隆升速率 (0.3~0.4m/ka) 相一致。

关键词: 川西高原, 杂谷脑河, ESR年代, 下蚀速率

Abstract:

Our field investigation identified eight river terraces at Zagunao, Lixian county of Western Sichuan Plateau along the Zagunao River, a main tributary of the Minjiang River. Applying ESR dating method, we successively determined ages of T2, T3, T4 and T6, which are 54, 125, 248 and 481 ka BP respectively. The development of the terrace sequences here was prominently under the control of regional tectonic uplift, and they should record phased uplift events of the Western Sichuan Plateau since the middle Pleistocene. The average incision rate of Zagunao River is calculated to be around 0.39 m/ka, which is coincident with the geodesic uplift rate of the Longmen Mountain (0.3-0.4 m/ka).

Key words: Western Sichuan Plateau, Zagunao River, ESR dating, incision rate