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TitleDeformation of quartzite experiment (2 of 2 photos)
DescriptionThin section of a quartzite experimentally deformed in axial compression at T = 1100 degrees C, P = 1.5 GPa, strain rate = 10-6/sec to about 50% shortening. The deformation mechanism was climb-accomodated dislocation creep with rapid grain boundary migration (regime 3 at Hirth and Tullis, 1992). The glide of dislocations is the strain-producing step and the recovery mechanism is dislocation climb, but due to the higher T the grain boundary mobility is much higher, and thus original grains are replaced by dynamically recrystallized grains at much lower total strain than is true at lower temperatures of deformation. Also, the recrystallized grain size is much larger. This texture is seen in quartzites naturally deformed at middle greenschist grade.
PhotographerJan Tullis. 1995.
CollectionKeck Structural Geology Slide Set #JT2.
Key wordsdeformation, quartzite
Tech details414 KB. Thin section.
GeoDIL number3061