Geological Survey Bulletin 1221-A Rockfalls and Avalanches from Little Tahoma Peak on Mount Rainier, Washington

Cover

Abstract

Introduction

Geographic and geologic setting

Description of avalanche deposits

Movement and velocity of the avalanches

Mudflows

Dust clouds

Cause of the rockfalls

References

1. Map of northeast side of Mount Rainier, showing area covered by avalanches from Little Tahoma Peak

2. General view of rockfall-avalanche deposits

3. Surface of avalanche deposits

4. Curved furrow in surface of avalanche unit

5. Block of breccia lying on Emmons Glacier

6. Aerial photograph of downvalley part of avalanche deposits

7. Map of downvalley part of the avalanche deposits

8. Damaged pine tree on terminal moraine

9. Avalanche scar at the base of Goat Island Mountain

10. Transverse cross sections of avalanche deposits

11. Longitudinal section of avalanche deposits

12. View of Little Tahoma Peak from Mount Ruth in 1956

13. View of Little Tahoma Peak from Mount Ruth, July 9, 1964

14. Diagram showing expectable points of impact of avalanche after it left Emmons Glacier

15. Cracked mounds on surface of mudflow deposit

16. Water vapor issuing from western base of rockfall scar on July 9, 1964

1. Comparison of Little Tahoma rockfall-avalanche deposits with others in the United States and Canada

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UNITED STATES DEPARTMENT OF THE INTERIOR
STEWART L. UDALL, Secretary

GEOLOGICAL SURVEY
William T. Pecora, Director

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