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Updated: Aug 12, 2026
09:12
A Method for Studying the Temperature Dependence of Dynamic Fracture and Fragmentation
Published on: June 28, 2015
Acoustically derived ice-fracture velocity in central Arctic pack ice
1Massachusetts Institute of Technology, Department of Ocean Engineering, Cambridge 02139, USA. caterina@mit.edu
The Journal of the Acoustical Society of America
|August 3, 2000
Summary
Fracture speeds in Arctic ice were estimated using acoustic events. Most fracture propagation speeds were found to be subsonic, differing from previous assumptions.
Area of Science:
- Geophysics
- Acoustics
- Cryosphere Science
Background:
- Fractures in Arctic ice generate acoustic events.
- Estimating fracture velocity is crucial for understanding ice dynamics.
- Previous studies assumed fracture speeds near Rayleigh wave speed.
Purpose of the Study:
- To estimate fracture propagation speed and orientation in Arctic ice.
- To analyze acoustic events using Doppler shifts from source motion.
- To compare estimated speeds with Rayleigh wave speed in sea ice.
Main Methods:
- Utilized acoustic event data from the 1994 SIMI experiment in the central Arctic.
- Analyzed data within the 10 to 350 Hz frequency window.
- Applied Doppler shift measurements to determine speed and orientation, assuming unilateral fracture propagation.
Main Results:
- Estimated fracture propagation speeds for 186 events.
- Found most speeds to be subsonic, ranging from 100 to 1100 m/s.
- Observed speeds significantly lower than the assumed Rayleigh wave speed of 1700 m/s.
Conclusions:
- Arctic ice fracture speeds are predominantly subsonic.
- The wide range of observed speeds suggests complex fracture mechanisms.
- Findings challenge previous assumptions about fracture propagation in sea ice.
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