摘要
太行山南缘的武家湾河流经太行山与华北平原两大地貌单元的过渡地带,较太行山内部其他水系对新构造运动的响应更为敏感,能较好地记录区域地壳抬升历史。以武家湾河下游平甸河为研究重点,通过野外河流阶地级序及沉积特征的调查并结合光释光(OSL)测年结果,厘定了平甸河4级河流阶地,T4、T3、T2及T1阶地河拔高度分别为61～96m、35～54m、19～43m、3～5m,分别形成于97.4kaB.P.、73.9kaB.P.、48.3kaB.P.、2.3kaB.P.,根据对阶地成因的探讨,认为T4、T3、T2阶地为构造阶地,T1阶地为气候阶地,阶地资料揭示晚更新世(Qp3)太行山南缘经历3次间歇性构造抬升后至少隆升了90m:第一次抬升26～42m、抬升速率1.11～1.79mm/a,第二次抬升11～27m、抬升速率0.43～1.05mm/a,第三次抬升16～39m、抬升速率0.35～0.85mm/a。本研究为河流阶地对新构造运动的响应研究提供了实际材料,对晚更新世太行山的形成及演化研究具有较重要的参考价值。
The responding to neotectonic movement in Wujiawan River,which runs through transition area of two geomorphic units of Taihang Mountains and the North China Plain,is more sensitively than other water systems in Taihang Mountains,so it can record the history of uplift better. By the field investigation of sequence and sedimentary features,dating of optical stimulated luminescence（OSL）,the conclusions can be reached that there are four levels of river terraces in Pingdian River,the lower reaches of Wujiawan River,T4 ,T3 ,T2 and T1 terraces’ heights are 61 96 m,35 54 m,19 43 m and 3 5 m,and ages are 97. 4 kaB. P. ,73. 9 kaB. P. ,48. 3 kaB. P. and 2. 3 kaB. P. respectively. After investigation the causes of river terraces,T4 ,T3 , T2 terraces should be the results of tectonic uplift,otherwise T1 is climatic terrace. It reveals that the amplitude of uplift of the area is 90 m at least after three stages of stable sedimentation and rapid uplift since Late Pleistocene（Qp3 ）,the amplitude and the rate of uplift are 26 42 m and 1. 11 1. 79 mm / a,11 27 m and 0. 43 1. 05 mm / a,16 39 m and 0. 35 0. 85 mm / a. This study is of great value,which provides actual material for the research of river terrace and neotectonic movement on the southern margin of Taihang Mountains.
出处
《现代地质》
CAS
CSCD
北大核心
2013年第4期791-798,共8页
Geoscience
基金
国家财政部与国土资源部"2011年国家级地质遗迹保护"项目(1212010712910)
