A new estimate of the conditions for transition from basal 〈a〉 to prism [c] slip in naturally deformed quartz
書誌事項
- 公開日
- 1995-11
- 権利情報
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- https://www.elsevier.com/tdm/userlicense/1.0/
- DOI
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- 10.1016/0040-1951(95)00039-4
- 公開者
- Elsevier BV
この論文をさがす
説明
Abstract Quartz c -axis fabrics of naturally deformed quartz in metacherts from the Ryoke metamorphic belt in the Yanai district, southwestern Japan, suggest that the prism [ c ], prism 〈 a 〉 and basal 〈 a 〉 slip systems were activated during the plastic deformation under high-temperature metamorphic conditions. With increasing temperature, quartz c -axis fabric patterns change from girdle type, through X -maximum with a faint crossed girdle, to X -maximum. The dominant orientation of subgrain boundaries in the quartz also changes from prism to basal with increasing temperature, closely correlated with the change in quartz c -axis fabric. The fabric transition is also accompanied by an abrupt increase of recrystallized quartz grain size. Moreover, observations with transmission electron microscopy (TEM) clearly identify the dominant activation of [ c ] slip through the presence of basal subgrain boundaries and free dislocations with the [0001] Burgers vector in the quartz from the metachert samples exhibiting X -maximum c -axis fabric. Based on these observations it is concluded that the mechanism switch from basal 〈 a 〉 to prism [ c ] slip systems occurred with increasing temperature in the metacherts. The transition temperature is petrologically estimated to be ca. 550–600°C at the natural strain rate.
収録刊行物
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- Tectonophysics
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Tectonophysics 250 (1-3), 31-46, 1995-11
Elsevier BV
