REPORT:
Volcanic Eruptions of 1980 at Mount St. Helens: The First 100 Days

Table of Contents

• In Dedication - David A. Johnston, December 1949 - May 1980
• Preface
• Abstract
• Introduction
• Cascade Range volcanoes
  • Table 1: Activity of major Cascade Range volcanoes
• Mount St. Helens Before 1980
  • Table 2: Summary of volcanic events and deposits formed at Mount St. Helens before 1980
• Perception and warning of the hazards
• Chronology of the first 100 days
  • Unusual earthquakes begin
  • Ash eruptions begin
  • Mountaintop cracks and craters grow
  • State of emergency
  • Eruptive activity decreases
  • Northern side bulges alarmingly
  • Eruptive activity resumes
  • Cataclysmic eruption
  • Continuing threats and mounting toll
  • Another explosive eruption and its aftermath
  • Third explosive eruption
  • Lava dome grows
• At the end of the first 100 days
  • Summary of conditions
  • Continuing hazards
• Outlook for the future
• Geologic hazard responsibilities
• Glossary of volcanic and related terms
• More about Mount St. Helens and other volcanoes

Return to:
[Report Menu] ...