Professor Sir Stephen Sparks CBE was Visiting Professor of Geology at Gresham College for the 2018/19 academic year. He is Chaning Wills Professor of Geology in the Department of Earth Sciences at the University of Bristol. He is one of the world's leading volcanologists and is widely recognised for his work in the field. His work is mainly focused on volcanic and igneous processes. He has also made contributions in fundamental fluid mechanics, sedimentology and risk assessment methodologies for natural hazards.