Monterey Bay Aquarium Research Institute

Factors controlling the styles of volcanic eruptions

Lionel Wilson, Ph.D.
Lancaster University

Wednesday, September 7, 2005
Pacific Forum – 3:00 p.m.

Volcanism is common throughout the Solar System. Eruptions on Earth take place under conditions limited by the range of pressures between the deep oceans (~30 MPa) and the tops of volcanic mountains (~75 kPa), with almost all well-studied eruptions being at the low end of this range. Eruptions on Venus took (take?) place at intermediate pressures (9 to 4 MPa), and current activity on Io, geologically recent activity on Mars, and ancient eruptions on the Moon involve pressures ranging down to hard vacuum. I shall show that thinking generally about eruption processes is a spur to model development, but point out that conditions on Earth's ocean floors (water is 20 times denser than the densest gas atmosphere—that of Venus) present challenges in deciding what physical processes dominate, with observations of the nature and distribution of eruption products being a critical input.

Next: The Transect Program: Metamorphosis of undergraduate students into ocean scientists