大别山东麓河流变形研究与郯庐断裂带活动性分析  

River Deformation in the East Foot of the Dabie Mountains and Activity Analysis of Tan-Lu Fault Zone

作　　者：杨源源[1,2] 赵朋 汪小厉[1] 姚大全 郑海刚 方震[1] 于书媛[1] YANG Yuan-yuan;ZHAO Peng;WANG Xiao-li;YAO Da-quan;ZHENG Hai-gang;FANG Zhen;YU Shu-yuan(Anhui Earthquake Agency,Heifei 230031,China;Key Laboratory on the Study of Middle –SouthernSegment of Tanlu Fault Zone,Anhui Earthquake Agency,Heifei 230031,China)

机构地区：[1]安徽省地震局,合肥230031 [2]郯庐断裂带中南段重点研究室,合肥230031

出　　处：《华北地震科学》2018年第4期16-24,共9页North China Earthquake Sciences

基　　金：安徽省公益性地质项目"郯庐断裂带(安徽段)重点地段第四纪新活动及介质速度结构探查评价"(2015-g-25);安徽省地震科技创新专项(CX201803)

摘　　要：基于数字高程模型(DEM),使用ARCGIS软件提取大别山东麓跨郯庐断裂带的河流及其纵剖面,并进行河流分级,结合遥感解译及野外调查研究不同级别河流跨断层的平面形态特征与纵剖面特征。研究发现:大别山东麓各级河流均无规律性变形,大多数河流纵剖面跨断层处不存在断层陡坎,河流T1级阶地跨断层连续分布无变形迹象,这些特征反映断层晚更新世以来可能不活动或活动微弱;调查了多个断裂露头,其中桐城挂车河基岩断层及太湖殷家上屋基岩断层中断层泥ESR年龄测试结果分别为(507±142)ka BP、(826±99)ka BP,综合大别山东麓河流变形特征、断层泥ESR年龄测试结果及前人研究资料,认为大别山东麓郯庐断裂带在中更新世存在活动,晚更新世以来可能不活动或活动微弱。The response of river to tectonic movement is very sensitive. The study of river topography can reveal the tectonic movement well. Based on Digital Elevation Model （DEM）, the ARCGIS software was used to extract the river and its profile across the Tan-Lu fault belt in the eastern foot of the Dabie Mountains and to classify the rivers. Combining remote sensing interpretation and field survey, we study the plane and longitudinal profiles of trans-fault rivers at different levels. It is found that there is no regular deformation direction at all levels of the eastern foot of the Dabie Mountains. Most of the vertical sections of the river do not exist fault horizons across the fault, and there is no deformation across the fault in the T1 class terraces. The above characteristics reflect that the fault may not be active or weak since the Late Pleistocene. A number of fault outcrops were investigated. The ESR ages of the fault mud in the Tongcheng Guache River bedrock fault and the Yinjia Shangwu bedrock fault in Taihu were （507±142） ka BP and （826±99） ka BP, respectively. Synthetically analysis of the deformation characteristics of the rivers in the foot of the Dabie Mountains and the ESR ages of the fault mud and the data from previous studies shows that the Tan-Lu fault zone at the eastern foot of the Dabie Mountains was active during the Middle Pleistocene and may be inactive or weak since the late Pleistocene.

关 键 词：大别山 河流 郯庐断裂带 活动性 

分 类 号：P315.2[天文地球—地震学]