Abstract
　A Geomorphological Land Classification Map Indicating Areas Subject to Flooding is intended to enable us to estimate the nature and extent of fioods, not only in the past, but also in the future. The reason why such survey maps indicate the features of floods is that the relief features of a plain and its sand and gravel deposits have been formed by repeated floods over the affected areas. Consequently, the micro-topography of the plain and state of sand and gravel accumulation can tell us the history of floods.
　With this proposal in mind I prepared "A Geomorphological Land Classification Map of the R.Brahmaputra-Jamuna and R. Ganges Plain" (Fig. 2) utilizing the LANDSAT images and the "Geomorphologic Map of the Brahmaputra Jamuna River Basin"(Fig. 3) by aerial photographs. Utilizing these maps I conducted research on the influence of the crustal movement and eustatic movement on the geomorphologic evolution of the plain, I have also researched the changes of the river course.
　I conducted the research on the features of the flooding caused by overflowing banks utilizing the LANDSAT images which was taken during the fiood in 1987. Furthermore I prepared land use map related with inundation and water table utilizing the LANDSAT images of 1983.
　Comparing the above mentioned three maps I propose policies of the mitigation of flooding in the area.

【キーワード】：水害，ガンジス，ブラマプトラ，地形分類
Key words: flood, Ganges, Brahmaputra, geomorphologic land classification

*早稲田大学教育学部
School of Education, Waseda University