USGS HOME
Contact USGS

  • About
  • Observatories
  • Activity
  • Education
  • Publications

Gas Hazards at Medicine Lake

Some volcanic hazards, such as concentrated accumulation of toxic gases, do not necessarily accompany the extrusion of magma. Before and during magmatic intrusions, and also during eruptions, gases, including carbon dioxide, sulfur dioxide, and hydrogen sulfide, can be transported to the surface. The closed topography formed by the caldera rim around Medicine Lake could allow toxic gases to pond during periods of extended calm wind conditions, potentially resulting in asphyxiation.