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An area of complex landslides is between the villages of Jarlang and Burang on the southeastern slope of Ankhu Khola valley, within the Ganesh Himal's southern flanks in central Nepal. Slow rotational rockslides within deeply weathered mica quartzites and schists have destabilized the head scarp composed of compact augen gneiss in Jarlang, causing rockslides from the main scarp. Successions of small rockslides (<10 6 m 3 ) have generated rather uniform deposits, whereas large, longrunout landslides (>10 6 m 3 ) have generated stratified deposits that have thin shear horizons.The recent erosional processes within the colluvial deposits, forced by rapid weathering of the deposits, include gully erosion and successive rotational and translational slides along the gully margins. The triggering event for the gullying and later gravitational slumping at Burang and Jarlang in 1954 was nine days of intense rainfall. The higher landslide activity within the Jarlang gully system is explained by reactivation along shear horizons in older landslide deposits.The yearly amount of mass wasting of both gullies divided by the area of the Ganesh Himal watershed yields an average rate of erosion of 6 mm/yr. This indicates that large-scale landsliding, and subsequent rapid erosion of the landslide deposits, could be the major denudation process within the Higher Himalayan range during interglacial time.

Within the southern flanks of the Ganesh Himal in central Nepal, an area of complex landslides lies in the Jarlang area, situated at the southeastern slope of the Ankhu Khola valley. Slow rotational rockslide in deeply weathered micaceous quartzites interlayering with mica schists have destabilized the head scarp composed of augen gneiss. It caused rockslides from the main scarp generating big spread-out landslides. The landslides of Jarlang generated a stratified deposit (> 106 m3) of matrix-poor breccias with thin fine grained shear horizons. The initial event for the biggest gully system in central Nepal was a gravitational slump owing to nine, day heavy rainfall in 1954. The recent processes within these colluvial deposits are torrential gully erosion accompanied by successive rotational and translational slides along the gully margins. The high activity within the Jarlang gully system can be explained by reactivation of the old Jarlang landslide's shear horizons. The slide grew from an original width of 300 m to 1.2 km at present, covering an area of 2.68 km2. The total volumetric loss by 1996 is l.46xl08 ml. The triggering factor for rock slides and rock falls generating big spread out landslides and debris slides and slope undercutting is seismic events due to extremely high uplift of the Himalayan Orogeny. The strong influence of human activities on slope stability and mass wasting as proposed in the Himalayan Environmental Degradation Theory can not be validated.