Poster So, how do ash aggregates form during tuff ring eruptions?... Volcanic ash is hazardous to people, animals, buildings, vegetation and the environment. Ash aggregation can result in the premature deposition of fine ash from volcanic ash clouds. Gaining insight into the process of ash aggregation will assist in the improvement of tephra fallout models. Ash aggregates form during explosive volcanic eruptions and are found in volcanic deposits worldwide. They consist of pyroclastic material that has adhered together forming pea-like structures. This poster summarised one aspect of my masters research project. The microstratigraphy of ash from a tuff ring in Tenerife is described and a model is presented for how ash aggregates form during tuff ring eruptions.