UPDATE: Landslides (General Observations)

July 6, 2015 by  
Filed under Geotechnical Impacts

Updated Map of Landslides Triggered by Ghorka Earthquake and Aftershocks
Posted by Patrick Bassal and Ashly Cabas


An updated landslide intensity map (including landslides caused by both the 25 April Ghorka Earthquake and the 12 May Dolakha Earthquake) has been posted to the Earthquakes without Frontiers blog. Approximately 5600 landslides have been mapped as of 10 June 2015.




Landslides have been a major problem since the earthquakes hit in Nepal. AGU’s landslide blog has a recent update concerning the Araniko Highway (a major link connecting Nepal with Tibet and China). Much of the highway has been littered with landslide debris, thus shutting down a necessary trade route. As the monsoon season is just underway, it will be critical to stay aware of the imminent landslide risks they may pose.

Some of the latest information concerning landslides in Nepal is being continuously updated in the following blogs:

Earthquakes Without Frontiers Blog (UK)

American Geophysical Union: The Landslide Blog


Landslide Hazard Analysis (University of Michigan)
Posted by Patrick Bassal and Ashly Cabas

Some researchers at the University of Michigan (U-M) have performed an analysis of landslide hazards associated with the recent Nepal earthquakes. Their analysis of landslide risk was performed using a computer analysis that looked at the earthquake ground motions, slope steepness, and strength of rock types. Their website contains downloadable “.kmz” files depicting the areas that may have experienced landslides or have an increased risk of landslides due to the earthquakes.


“Information from the U-M-led study has been shared with the U.S Geological Survey, NASA, the U.S. Agency for International Development and other responding agencies. It is being used help prioritize both satellite observations and the analysis of data from those satellites, said Clark, an associate professor in the U-M Department of Earth and Environmental Science.”


More information and downloadable content is provided in the links below:


April 28, 2015 Landslides News Release (U-M)


U-M Nepal Earthquake Data/Download Site


Preliminary Map of Landslides Triggered by Earthquake
Posted by Patrick Bassal


Research groups in the UK have been working to identify large landslides that are blocking valleys, affecting villages, and disrupting the infrastructure in Nepal. Their observations are based on satellite imagery taken from multiple sources (see map posted below). Their preliminary findings and recommendations for field study can be found in the Earthquakes Without Frontiers link below. One of the most significant observations is that the zone mapped to have intense landsliding corresponds to areas with high rates of past landslides triggered by rainfall. It is thus necessary to assess the hazard associated with these potential landslides before the upcoming monsoon season, expected to start in late June.
Source: http://ewf.nerc.ac.uk/blog/

Source: http://ewf.nerc.ac.uk/blog/