汉江郧阳段河流阶地发育特征及新构造运动意义

发布时间：2018-03-30 17:10

本文选题：汉江郧阳段　切入点：河流阶地　出处：《大地测量与地球动力学》2017年02期

【摘要】：在野外调查的基础上,分析汉江郧阳段河流阶地的发育特征。结合地质、地貌及第四纪测年学资料,推断汉江T_1~T_5阶地形成的时代分别为全新世-晚更新世末期(约25ka BP)、晚更新世(约67ka BP)、晚更新世早期-中更新世末期(约128ka BP)、中更新世早期-早更新世晚期(约1 344ka BP)、不晚于早更新世。阶地的横向对比显示,两陨断裂的活动导致汉江五峰段、青曲段、郧阳盆地段T_3、T_2阶地在垂向上构造隆升的差异性,结合T_3、T_2阶地的形成时代,推测断裂活动的时代为中更新世末期-晚更新世早期。近似地推算汉江郧阳段更新世早期以来的平均隆升速率约为0.052mm/a,显示抬升速率及幅度较秦岭弱,可能由于汉江郧阳段处于秦岭东南缘余脉,并非秦岭隆升的中心地域。
[Abstract]:On the basis of field investigation, the development characteristics of river terraces in Yunyang section of the Hanjiang River are analyzed, combined with geological, geomorphological and Quaternary dating data. It is inferred that the T_1~T_5 terrace of the Hanjiang River was formed in the Holocene to the end of the late Pleistocene (about 25ka BPU), the late Pleistocene (about 67ka BPU), the early Pleistocene to the end of the Middle Pleistocene (128ka BPU), the early Middle Pleistocene to the late early Pleistocene (about 1. The horizontal comparison of the terraces of 344ka, no later than the early Pleistocene, shows that. The activity of the two meteorite faults resulted in the difference of the vertical uplift of the TSP _ 3 / T _ 2 terrace in the Wufeng, Qingqu and Yunyang basin sections of the Hanjiang River, and combined with the formation age of the T _ 3T _ T _ 2 terrace. It is inferred that the age of fault activity is the late Middle Pleistocene to the early late Pleistocene. The average uplift rate since the early Pleistocene in Yunyang section of the Han River is estimated to be about 0.052 mm / a, indicating that the uplift rate and amplitude are weaker than those in the Qinling Mountains. It is possible that the Yunyang section of the Hanjiang River is located in the remaining veins of the southeast margin of the Qinling Mountains and is not the central area of the uplift of the Qinling Mountains.
【作者单位】：中国地震局地震研究所(地震预警湖北省重点实验室);武汉地震工程研究院;
【基金】：中国地震局社会公益研究项目(1521401800062)~~
【分类号】：P546;P931

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