| One of the most great geosciences discoveries in the past20year is arguably the recognition that there exists a dynamic coupling between climate-driven erosion and tectonics. There are many researches about the interaction between tectonic, climate and landforms were appeared during this period. Organic topography is very important, which controlled by tectonic activity, climate change and surface processes together, Studying tectonic geomorphology and surface processes is going through the traditional qualitative thinking by "observation-Description-reasoning" to the quantitative research through development of physics experiments and mathematical models. Among them, the digital elevation model (DEM) and GIS spatial analysis methods are widely used in two core issues about tectonic geomorphology: quantitative research and process simulation. Lushan is a moderate hill which area less than300km2and has a warm and humid climate. First, we have made a fundamental digital terrain analysis in Lushan, including slope analysis, elevation analysis and swath analysis, based on5m resolution DEM data. Second, in order to explain the causes of the current tectonic activity of the Lushan, we have introduce many topography parameters, such as K, AFreiative, HI, Smf, Rb, Bs, SCI and Ksn, for investigate the relative tectonic activity and uplift mode. Finally, we discuss the different stages of geomorphic evolution and spatial differences. The basic conclusions are as follows:(1) The best analysis window about the local relief is16000m2based on5m resolution DEM data and the conclusions about relief analysis and slope analysis are consistent. The critical slope is37°and the hillslopes will play the main role when the slope above this critical slope. There are two plantain surfaces on the Peak of Lushan Mountain, which surface elevation is1300m-1400m and1000m-1200m respectively.(2) Strong tectonic activity in Lushan mainly distribute in E06, El2and W10. Moderate tectonic activity in Lushan mainly distribute in central basin, such as west valley and central basin. The rest relatively tectonic activity is weak, such as the Wangjiapo valley, Lushanlong valley and so on. Ksn indicate the tectonic uplift rate and the average of Ksn is140in the center of Lushan, corresponding uplift rate of1.12±0.2mm*yr-1. There are three level Knickpoint on the river longitudinal profile(respectively, height300m,500m and800-900m),which indicates that since the Pliocene Lushan made at least three times fast block uplift, the largest uplift mount of the mountain in central Lushan, about900-1200m.(3) The spatial distribution of HI between5m and30m resolution DEM data are consistent. HI always controlled by the position of analysis window and the size of analysis window and we have the same conclusions about the distribution of HI by many kind of analysis window. The biggest HI is distributing on the top of the mountain, which is the main source of the river. This means that geomorphic evolution of landforms are in the infancy and the middle reaches of the river where geomorphic evolution are in the mature stage and the old age geomorphic surfaces developed on both sides of the lowland plains in the foothills of the mountains. Combined with HI, HC and EP, we put it into geomorphic evolution and quantitative analysis which is basically reliable. |
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