Langtang village avalanche / landslide
The earthquake of 25 April has presumably triggered a large avalanche / landslide which has buried the Langtang village under debris. On 25 April during the earthquake a helicopter of Simrik air was on its way to Langtang and Jason Laing on board of the helicopter made a picture of Langtang village complete covered under debris (Annapurna Post article). Using high resolution imagery of DigitalGlobe from before the earthquake we tried and identified the shape of the fields visible and numbered in the picture and on the map.
Langtang village was located below a very steep ridge and above the ridge there is a glacier towards the north-west and large snow field right above the village. There has been a lot of snow fall this year and at the moment of the earthquake there were considerable amounts of snow at higher altitudes. From a preliminary investigation we think it is most likely that either a snow avalanche from directly north of Langtang village or a debris/ice avalanche from the north-west has caused this disaster. These are marked by red arrows in the map.
Once post-earthquake imagery becomes available, we will be able to confirm the cause and detect further river blocking in the valley which may cause large lakes to form and could be a potential threat for the future.
To have look at post-earthquake satellite imagery check this follow-up post:
‘Landsat 8 reveals extent of earthquake disaster in Langtang Valley‘
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