Slope Instability in the Eastern Kharkhiraa Uul


Pat Kailey

Whitman College, Walla Walla WA 99362

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The slopes of the Eastern Kharkhiraa Mountains are currently undergoing a period of dramatic instability triggered by climate change, increased runoff from mining operations, and/or overgrazing. Ten to twenty degree vegetated slopes with large accumulations of colluvium fed by talus upslope are the most susceptible to failure. Earth flows are 10-20 m wide with convex, vegetated toes 1 m high undergoing solifluction. Debris flows are characterized by natural levees and occur on steep slopes and valleys. Many slopes and valleys exhibit multiple generations of mass wasting. Peat beds (up to 10 cm thick) alternating with loess, alluvium, and/or colluvium indicate cycles of stability-instability which may represent changes in paleoclimate.