Geomorphologic analysis of catastrophic floods of Madarsoo River (North-Eastern Iran

Madarsoo is a major tributary of Gorganrood River, draining an area about 2150 km2 South-East of Caspian Sea. Intense floods of Madarsoo River (Dogh) in 2001, 2002 and 2007 can be considered as catastrophic floods. The flood which happened in 2001 is considered as a starting point of a new period of geomorphic crisis in the region. This flood affected the whole drainage basin and its intense morphological change confirms new catastrophic opinions in periodic evolution of relives. After an analytical study of geomorphic floods, this paper considers the geomorphic effects of these catastrophic floods in comparison with ordinary floods (bank full discharge) in a regional scale. Considering the similarity of geomorphic effects of recent floods with the existing evidences provided from palaeofloods, an idea can be presented that a passing period of climatic change has started in the region and it will be accompanied with significant geomorphic problems. Therefore a conscious treatment is needed for adjusting flood control projects and reconstruction of natural environment.