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Updated: Jun 28, 2026
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A Method for Studying the Temperature Dependence of Dynamic Fracture and Fragmentation
Published on: June 28, 2015
Summary
Laboratory seismic velocity measurements confirm theoretical predictions of crack growth during rock dilatancy. Dilatancy was observed to decrease seismic velocity ratios via undersaturation and liquid-gas phase transitions.
Area of Science:
- Geophysics
- Rock Mechanics
- Seismology
Background:
- Seismic velocities are crucial for understanding rock properties and subsurface structures.
- Dilatancy, a phenomenon of rock expansion under stress, significantly influences seismic wave propagation.
- Previous theories predicted crack growth effects on seismic velocities during dilatancy.
Purpose of the Study:
- To experimentally validate theoretical predictions of seismic velocity changes during rock dilatancy.
- To investigate the mechanisms by which dilatancy affects seismic compressional and shear velocities.
- To explore the role of undersaturation and phase transitions in dilatancy-induced seismic velocity changes.
Main Methods:
- Conducting laboratory experiments on rock samples under controlled deformation.
- Measuring seismic compressional and shear velocities during the deformation process.
- Analyzing the relationship between crack growth, dilatancy, and seismic velocity ratios.
Main Results:
- Experimental seismic velocity data showed strong agreement with theoretical predictions.
- Observed a decrease in the ratio of seismic compressional to shear velocity during dilatancy.
- Identified undersaturation and liquid-gas phase transitions as key mechanisms causing this velocity ratio drop.
Conclusions:
- Laboratory measurements confirm theoretical models of crack growth effects on seismic velocities.
- Dilatancy demonstrably alters seismic velocity ratios through specific physical mechanisms.
- Understanding these mechanisms is vital for accurate seismic interpretation in geological settings.
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