摘要
通过卫星影像解译、野外实地调查与地质填图,对甘肃东南部迭部—白龙江南支断裂中东段晚第四纪构造活动特征进行了研究。结果表明:迭部—白龙江南支断裂中段活动性明显强于东段;中段线性特征明显,可见清晰的断崖,不同期次的阶地之上都有断层陡坎发育,晚第四纪以来有过明显活动,最新活动的离逝时间为1 300年左右,属于全新世活动断裂;东段活动性明显减弱,没有发现断错全新世地层的证据,在地貌上多表现为线性沟谷,属于晚更新世断裂。根据对断错阶地的测量和年代测试,迭部—白龙江南支断裂中段左旋滑动速率为每年(1.3±0.1)mm,垂直滑动速率为每年(0.39±0.04)mm。
Based on satellite image interpretation, field survey and geological mapping, the characteristics of Late Quaternary tectonic activity in the middle-eastern segment of the southern branch of Diebu-Bailongjiang fault, Gansu, were discussed. The results show that the activity of the middle segment of the southern branch of Diebu-Bailongjiang fault is stronger than that of the eastern segment; the characteristic along the middle segment is significantly linear, and the scar and fault scarp cutting through several terraces can be easily distinguished; the middle segment is active since Late Quaternary, and the elapsed time of the last event should be less than about 1 300 years; the middle segment is Holocene active fault; the activity of the eastern segment is obviously weakened, and there is no evidence of Holocene fault; the landform in the eastern segment is a linear valley, and the eastern segment is Late Pleistocene fault. According to the measurement of fault terrace and dating, the left-lateral and vertical slip rates are （1.3±0.1） mm and （0. 39±0. 04） mm per year in the middle segment of the southern branch of Diebu- Bailongjiang fault.
出处
《地球科学与环境学报》
CAS
2015年第6期111-119,共9页
Journal of Earth Sciences and Environment
基金
中国地震局地震预测研究所基本科研业务费专项资金项目(2011IESL01)
"十二五"国家科技支撑计划项目(2011BAK12B05)
