| The formation of geomorphology is controlled by regional tectonic activities,and the deformation results of regional geomorphology can reflect regional tectonic activities and evolutionary history.The southern section of Taihang Mountains is located in the transition area between Loess Plateau and North China Plain,and is in a more complex geological and tectonic area.Since the Cenozoic belt,it has been under the dual influence of subduction of Pacific plate and Indian plate,and has strong tectonic activity,which has a controlling effect on the landform.The 1830 magnitude 71/2 earthquake inMagnetic County occurred in this area.No major earthquakes have occurred in this area for a long time recently,and there is a lack of attention,especially the uplift magnitude and period of the southern section of the Taihang Mountains since the Quaternary is still somewhat controversial,and the activity of the Jinhuo fault has not been adequately studied.In order to study the differences of tectonic landforms in the southern section of the Taihang Mountains,this paper explores the evolutionary stages of landforms in the region through indoor remote sensing interpretation and GIS platform using various landform indices;the macroscopic topographic parameters(slope and slope spectrum,roughness,cut,undulation),fluvial landform parameters(HI index)and strip profiles are used to analyze the macroscopic tectonic landforms in the southern section of the Taihang Mountains;remote sensing image The development level,draw height and age of the river terraces of Qinhe,Danhe,Zhanghe,Lushui,Qishui,Xishui,Zifang and Pingdian rivers in the southern section of Taihang Mountains were defined by remote sensing image interpretation,UAV remote sensing data,field terrace survey and previous research data,and the relationship between tectonic activities in the southern section of Taihang Mountains since the Quaternary was discussed;based on remote sensing image Based on remote sensing image interpretation,UAV flight,DEM data analysis,field survey,borehole information and previous studies,the activity of the south-central section of the Jinhuo Fault was studied and analyzed,and the following understanding was obtained.(1)The slope,roughness,cut,and undulation of the southern section of Taihang Mountains show high values on the eastern side of the southern section of Taihang Mountains,and the parameters are obviously higher than those on the western side,and the area of high values is consistent with the trend of the fracture at the eastern foot of Taihang Mountains,which shows the control of the fracture on the landscape;the HI values of the southern section of Taihang Mountains watershed indicate that the landscape of the southern section of Taihang Mountains is in the juvenile-juvenile development stage,and the overall tectonics is in the active stage.(2)At least three phases of tectonic uplift occurred in the southern section of the Taihang Mountains at 1.7Ma,namely the late Early Pleistocene,Middle Pleistocene and Late Pleistocene,with six phases at 1.7Ma,0.8Ma,0.1Ma,0.07Ma,0.05Ma and 0.03Ma.The uplift rate has gradually accelerated since 1.7Ma,and the average uplift in the southern section of the Taihang Mountains since 2.6Ma is 166-285 m.The maximum uplift is not more than 300 m.166-285 m on average since 2.6Ma,with the maximum not exceeding 300 m.Therefore,the Quaternary is not the main uplift stage in the southern section of Taihang Mountains.(3)The middle section of Jinhuo fault is oriented to NNE,a positive fault,with a fault distance of about 500 m since the Pliocene and an activity rate of 0.09mm/a.According to the information of borehole and fault profile,the activity of the fault is strong in the early Pleistocene and weak in the middle and late Pleistocene;the southern section of Jinhuo fault is oriented to NNE,a positive fault,with strong activity in the early Pleistocene and weak activity in the middle and late Pleistocene. |
PDF Full Text Request