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Abstract: The aim of this paper is to investigate the morphological implications of the interplay between tectonic movements at different rates, timescales, and spatial extent in a catchment of intermediate size, the Huang Shui River (a main tributary of the Yellow River in the NE Tibet Plateau). River incision started from a peneplain-like surface that developed in post-Miocene–Pliocene times. At the end of the Tertiary, a general tectonic uplift of the Tibetan Plateau initiated river incision. This general uplift also caused local fragmentation of the Huang Shui catchment into blocks (kilometers or maximally, a few tens of kilometers) of local extent that have subsided and/or uplifted relative to one another. Fluvial deposition of >30m in the subsiding blocks contrasts with erosion and formation of gorges in the uplifted blocks. Incision into the former peneplain was not continuous but a staircase of terraces developed under climatic influences. Terrace deposits are sometimes capped by interglacial soils or soil-derived material. Apparently, terrace incision occurred at the transition to the next cold period. The different rates of uplift and subsidence of the individual blocks resulted in the simultaneous development of erosion and accumulation terraces of different sizes within the same catchment, even within the same tectonic block. This makes it impossible to connect the terraces of the different blocks, except for the three youngest terraces (representing the last 300,000years), thus illustrating the uniform tectonic history of the catchment since that time. [Copyright &y& Elsevier]

On April 9, 2000, a super-large landslide (3×108 m3) occurred along Zhamu Creek, southeast Tibet. As a result, a landslide dam formed and the Yigong River was blocked. A channelized diversion was constructed for prevention of overtopping. Two months later on June 10, a catastrophic flood resulting from the failure of the landslide dam caused a serious loss of property. This is the second of landslide occasion dam formation and flooding occurrence at the same site since 1900.In this paper we introduce the background and occurrence of the landslide, report the dam failure and overflow process, and finally discuss the origin of the landslide and of the flood in comparison with statistical characteristics of previous case histories worldwide. Many large and small landslides will continue to occur because of the distinctive physiographic, geological and climatic conditions in this region. What we can do is perhaps only to predict and avoid them. With predicted global warming, water availability has become more and more important for landslide occurrence. [Copyright &y& Elsevier]