Kinematic characteristics of pyroclastic density currents at Merapi and controls on their avulsion from natural and engineered channels.

The article reports on a pyroclastic density current avulsion at Merapi, Indonesia in June 2006, which featured four multiple dome collapses that led to four individual block-and-ash flows into the Kali Gendol valley. A sabo dam can significantly increase the potential of flow avulsion. The article states that a model derived from data and observations can be built to obtain kinematic qualities of the valley avalanches and flows, which are otherwise hidden by ash clouds.