4 September 2018

Boulder roll – a surprising video (updated with location)

Posted by Dave Petley

Boulder roll – a surprising video (now updated with the location)

I have posted previously about the hazards associated with rolling and jumping boulders, and the damage that they can cause.  Generally speaking we think of the greatest hazard being posed by boulders traveling down long, steep slopes, and thus having very high kinetic energy.  However, this is not necessarily the case. A video has emerged, and been posted to Youtube, from Uttarakhand in the last few days that shows that even boulders without long fall heights can be extremely dangerous:-


This is a very nice example of a boulder roll.  There is really not much information on Youtube about where this happened, other than being within Uttarakhand in northern India. But the video includes a location sign, and in a pair of comments below reader Anne Roseveare indicates that these names translate to: Sama, Liti, Tejam and Namik.  She indicates that this means that the area can be found in this link to Googlemaps.

The video suggests that this is a deeply weathered slope, which possibly has been cut for the road.  The large boulder is released by the slope, and manages to achieve significant speed despite the low fall height.  Clearly this would be exceptionally dangerous for road users:-

boulder roll

A still from a Youtube video showing a boulder roll event in Uttarakhand in northern India. The video was posted on 28th August 2018.


I think that this video should be required viewing for those who are willing to cut slopes without thinking of the potential consequences.