EFFECT OF GRAIN SIZE ON ROCK DEFORMATION IN DUCTILE SHEAR ZONE
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摘要: 构造模拟研究表明, (1) 粒度是控制岩石流变性质的重要因素之一, 粒度越粗, 岩石粘度越高; (2) 粒状矿物含量与基质的比值越低, 粒度对岩石流变性质的影响就越小, 反之则越大; (3) 岩石的粒度差异对韧性剪切带的发育程度有着重要影响, 粒度越细, 韧性剪切带中有限应变越大.这些结果与野外所观察的地质现象及应变测量结果完全一致.Abstract: The tectonic simulation research indicates: (1) The grain size is one of important factors controlling the rheological behaviors of a rock. The coarser the grain of minerals in a rock, the higher the viscosity of the rock. (2) The lower the ratio of the granular mineral content to the matrix, the smaller the effect of the grain size to the rheological behaviors of the rock, and vice versa. (3) The difference between grain sizes of a rock affects greatly the development of a ductile shear zone. The finer the grain size, the greater the finite strain in the ductile shear zone. These conclusions are perfectly consistent with the geological phenomena observed in the field and the actual measurement of finite strain of rocks in the ductile shear zone.
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Key words:
- ductile shear zone /
- grain size /
- rheological behavior of rock /
- tectonic simulation
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表 1 不同模型材料流变测试结果
Table 1. Measured rheological deta from different model mate-rials
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