Features and genesis analysis of Danxia landscape in the northwest foothills of the Wuyi Mountains

Intense faulting tectonic activity occurred in the Cretaceous to Paleogene period in the northwest foothills area of the Wuyi Mountains, forming a series of red-faulted basins along the regional fracture zones and depositing a set of red terrestrial clastic rocks, which include Xinjiang, Nancheng, Nanfeng, Ningdu, Shicheng, Ruijin and Huichang basins distributed from the north-east to the south-west. These basins are obviously controlled by NNE-oriented faults, and all of them are small fracture basins except for the slightly larger Xinjiang basin in the north. With the swell of the South China region since the Cenozoic, the red strata in the basin was uplifted, and numerous Danxia landscapes were formed under the geological effects of internal and external dynamics such as tectonics and rivers. Due to the differences of the lithology, tectonics and river erosion intensity of the red strata, diverse forms of Danxia landscapes have been formed in different basins and undergone various evolutionary stages. Field geological and geomorphological investigation and comparative studies show that the Danxia landscapes in the area can be divided into six types according to morphological features: peaks, steep cliffs, collapse bodies, canyons, caves and others. Indicated by the area elevation integration and multi-level buffer zone analysis, the evolution of Danxia landscapes in this area show a trend of getting younger from north-east to south-west, and its genesis is correlated with the spatial differences under the conditions of red strata, fault activities and river development, which together constitute the formation system of Danxia landscapes in the northwest foothills of the Wuyi Mountains.