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Updated: Jul 11, 2026
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High-pressure, High-temperature Deformation Experiment Using the New Generation Griggs-type Apparatus
Published on: April 3, 2018
Deformation twins in hornblende.
Science (New York, N.Y.)
|July 10, 1970
Summary
Hornblende single crystals were experimentally deformed to create twinning. This occurred under specific high-pressure and high-temperature conditions, revealing new insights into mineral deformation mechanisms.
Area of Science:
- Mineral Physics
- Geology
- Materials Science
Background:
- Hornblende is a common rock-forming mineral.
- Understanding its deformation mechanisms is crucial for interpreting geological processes.
Purpose of the Study:
- To experimentally produce and characterize deformation twins in hornblende single crystals.
- To investigate the conditions under which twinning occurs in hornblende.
Main Methods:
- Single crystals of hornblende were subjected to compression experiments.
- Experiments were conducted at confining pressures ranging from 5 to 15 kilobars.
- Temperatures were controlled between 400 and 600 degrees C with a strain rate of 10^-5 s^-1.
Main Results:
- Deformation twins with twin planes parallel to (101) were successfully produced in hornblende.
- Twinning was observed under the specified high-pressure and high-temperature experimental conditions.
Conclusions:
- The study demonstrates the feasibility of creating hornblende deformation twins under controlled laboratory conditions.
- These findings provide valuable data for understanding the rheology and deformation behavior of amphiboles in the Earth's crust and mantle.
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