| Chishui Danxia is located in the distribution area of Danxia between Sichuan Basin and Yunnan-Guizhou Plateau, it is plateau-canyon Danxia landscape that rare develop in the southern margin of subtropical giant red bed basin. For there is a lack of basic research of Chishui Danxia landform formation and protection, through project work, field investigation and indoor analysis, literature review and other methods, this paper made research about development dynamic system, forming process and morphological types, world heritage value and protection to Chishui Danxia, draw the following conclusion and discussion:1. Red layer of Chishui Danxia landform is formed in the southern marginthe of "Bashu ancient lake", namely the Sichuan red basin edge, is lacustrine red clastic rocks deposits of 3000~4000m in the Mesozoic, with cold, dry, warm and humid climate. After a long and complex geological structure evolution, Chishui Danxia landform areas formed structural system mainly from north to South and east to west, types of short axis anticlines and dome structure, including Guandu anticline, Wanglong anticline, Tucheng nose shaped anticline, Moziyan anticline, Dabaitang syncline, Yanziyan syncline, trunk field syncline. And affected by tilting uplift, joint clouds in the area. These tectonic line pattern control block pattern and block mountain shape of Chishui Danxia Mountain, large tectonic line control the overall orientation of mountain blocks, small structure control block mountain direction, density and flat morphology, different direction of joint make Danxia Landforms more diverse. The mountain block of Chishui Danxia landform area extends along the direction of the north to south and the east to west, and the stone pillars are arranged along the joint.2. Forms of new tectonic movement in Chishui Danxia area are mainly multilevel river terraces, waterfalls and multi-level planation surface. Multi-level river terraces were found in the southern margin of Chishui City and Xishui County Soil town in the Chishui River valley open a little place that in the recent geologic time in three crustal intermittent rise. In Chishui area, with humid climate, rugged terrain, numerous rivers, waterfall is very well developed, mainly along the Chishui River. Influenced by the intermittent uplift of new tectonic movement, Chishui Danxia area formed six levels of planation surfaces, 1300-1400 meters planation surface, 1000 ~ 1200 meters planation surface, 800 ~ 900 meters planation surface, 600 to 700 meters planation surface, 500 meters planation surface, 300 meters planation surface. Characteristics of new tectonic movement can also be specific depth to water, mountain formation, alluvial fan, river longitudinal profile shape of landform, new tectonic fault geological features, recommends that future research can continue to explore.3. Erosion is the outside dominant power of Chishui Danxia landform, including water erosion and rain erosion. Weathering exposed of red bed slope is a regular damage, the differences between soft and hard rock weathering formed Danxia honeycomb solution cave landscape. The dissolution of the red layer containing carbonate on the development of stalactites, stalagmites and columns of Danxia Karst landscape. Biological role on the one hand, slowing the weathering of rock., on the other hand the rock surface end skin weathering, the cliff retreating; while growing up in the rock surface of plant color is rich and changeful, which also makes Danxia cliff more colorful. The effect of gravity collapse accelerated the erosion, weathering, corrosion and biological effect. On the basis of this research still need to sample the fixed-point observation, model analysis of various external dynamic mechanism.4. The red beds of Chishui Danxia landform area are mainly formed in the Jurassic, and the Danxia landform is formed in the Neogene. Chishui Danxia landform is mainly developed in depressed area of the Yangtze plate, through the pre Sinian Jinning movement, the Caledonian movement at the end of the Silurian and early Indosinian movement in Triassic, early Yanshan movement at the end of the Jurassic, early Himalayan mountain movement in new Paleogene, and recorded crustal evolution history, change of geographical environment and climate change process of Chishui Danxia since the Jurassic. Chishui Danxia landform morphologies, developmental process, dynamic mechanism and climate and geographical features unique, with the earth’s land surface system of global change comparative study and the earth since the Mesozoic major geological events contrastive study value. It gave birth to the landform known in China Danxia(red beds) landscape scale is biggest, the elements of the most complete and contains a variety of typical and prominent of the rare and endangered plant and animal species and their habitats, historical and cultural heritage in its unique way fusion in natural beauty, constitute the most distinctive example of harmonious coexistence of man and nature. River terrace alluvium recorded the tectonic evolution and ancient geographical environment in this region, suggest in the future research set up special project, further refined and summarized Chishui Danxia landform evolution and history.5. On the macro, Danxia Chishui can be divided into the early youth of plateau canyon area and the late youth of mountain canyon area. Early youth plateau gorge is located in the west side of Chishui River, and maintain a continuous original sedimentary top surface, the erosion amount is less than 20%; the eastern side of Chishui River is late adolescence mountain canyon area, the top surface reduce, original flat top surface is less than 30%, an amount of soil erosion is 20-40%.Chishui Danxia has diverse geomorphologic types, it formed more than 10 kinds of positive and negative geomorphology, which had high scientific and aesthetic value; it develops early rejuvenated young stage of Danxia landform of the unique eroded middle mountains, low middle mountain, low mountains and hills in wet and hot sub-tropical monsoon region, presents geomorphological combination of the plateau/mountain gorge landscape. The mechanism of soft and hard rock to the grooves, honeycomb solution points to the formation of fine special research is needed and further refined and summarized the origin cause of formation of the Chishui Danxia landform.6. By contrast to the global analysis of Chishui Danxia landform, Chishui Danxia due to its uniqueness, integrity, typical, high value has an irreplaceable role in red bed(Danxia) landform, meet world heritage VIII standard, have outstanding universal value of landform. Chishui Danxia landform is currently facing the threat of the mountain collapse, landslide and debris flow and other natural factors, engineering construction, water pollution, tourism activities and weak protection awareness of the residents and other human activities, heritage value continue to reduce. According to the different threat factors, the corresponding protection measures are conducive to the protection and utilization of the Chishui Danxia landform value, and take the heritage resources to future generations. |
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