This collection of papers is based on a symposium held in 1987 at the Interna tional Union of Geology and Geodesy Congress in Vancouver, British Colum bia. The Symposium was planned as a follow-up to a session at the 1984 Geo logical Society of America Annual Meeting in Reno, Nevada, which dealt with the emplacement of silicic lava domes. In both cases, emphasis was placed on the physical and mechanical rather than chemical aspects of lava flow. The IUGG Symposium consisted of two lecture sessions, a poster session, and two discussion periods, and had 22 participants. The contributions to...