Moraine dam stability analysis of Ngozumpa glacier in Gokyo area, Nepal

Abstract:

The study site is located in the Gokyo area, which is situated in a glaciated region. Ngozumpa Glacier is the main glacier, where many small supra-glacial lakes are formed. Gokyo village is located on the outer(southern) slope of right lateral moraine of the Ngozumpa Glacier and Gokyo Lake is formed in front of the village. The main aim of the research is to assess the stability of the lateral moraine of the Ngozumpa Glacier in and around the Gokyo village. Field evidences reveal that inner slope of the lateral moraine is unstable with several rotational slides, while outer slope is in better condition than that of the inner slope. Fine sediments of the lateral moraine were sampled for laboratory analysis. Laboratory results are used as input parameters to test the stability of the dam at outer and inner slopes using Morgenstern Price Method. Laboratorial data corporate the output of model with field evidences. The study has proved that the stability of the moraine condition of the Ngozumpa Glacier is safe in the present condition found from the analysis of moraine properties, laboratory test and modeling through the Geo-slope studio software(2012) in slope /W.

Keywords: Ngozumpa glacier, Moraine deposit, Stability, slope/W, Stable.