Massive Landslide inside the Askja Caldera

Deposits and scarp from the July 21, 2014 landslide in the Askja caldera, Iceland. Photo by Capture from RUV.is video. Most volcanoes are inherently unstable features. They are constructed of loose piles of volcanic debris (tephra) and lava flows on relatively steep slopes. This means that they can be prone to landslides. This is especially so inside calderas, a depression formed by the collapse of the land surface. The inner slopes are usually steep and crumbly, leading to the formation of weakened zones along the edges of the caldera. Landslides, triggered by earthquakes or merely due to gravitational forces on the slopes, can then happen, sending debris into the caldera. If its filled with water, then you can even get tsunamis within the caldera itself. It appears that just such a large landslide occurred on July 21, 2014 at Iceland's Askja (see above). The Askja caldera was formed during an ...