RS And GIS Based Geomorphic Processes Of Zhangjiajie Geopark, Hunan Province

Zhangjiajie sandstone peak forest world geopark is located in Wulingyuan district,Zhangjiajie,northwest Hunan province,China.It is famous for majestic beautiful sandstone peak forest in the world. Many experts and scholars concern about this particular geological landforms.They mainly concentrated in the landform genesis and geomorphic processes.With the deepening of the research, the experts and scholars gradually have reached an agreement on landform genesis,however,the gemorphic processes of sandstone landforms still exist problems.There is no system theory about geomorphic processes of Zhangjiajie geopark.It is lack of study since the start of formation.Using the research methods of modern geomorphology, this paper, with the help of remote sensing technology ,process Landsat ETM + images.Landsat ETM + contains seven bands.In order to avoid the band information redundancy,we statistic each band spectrum information in remote sensing software ENVI,and compare various band of information,and use the OIF method to evaluate the relevance of each band.Finally,we choosed ETM + 7, 4, 3 bands.Image processing methods include image enhancement and image fusion etc.On this basis, this paper visual interpret landforms, streams and the geological structures of study area.In order to assist the interpretation,We have builded 3D terrain model with GIS.Based on the analysis of the results of interpretation,this paper analyze controlled factors of Zhangjiajie sandstone landforms.According to Zhangjiajie sandstone landforms superimposed folds and linear structures by using GIS platform,this paper inferred tectonic setting of sandstone landform.We analyzed geomorphic distribution of sandstone, especially the relationship with water,and compared landform surfaces of study area and layered landform surfaces.The article concludes the formation process of sandstone geomorphology.The study suggests that the research area first undergo Indo-Chinese Epoch fold movement and Yanshanian fold movement.In this basic structure pattern,the area shape an erosional surface and a planation surface.Himalayan periods,earth crust intermittent uplifts,downcutting erosion and headward erosion were enhanced,then,forming the present Zhangjiajie sandstone landform.