Experimental analysis of ductile-slip rheology in shallow structural level faults

Science in China Series D: Earth Sciences - Tập 44 - Trang 481-489 - 2001
Benliang Li1, Liangshu Shu1, Yan Sun1, M. Faure2, J. Charvet2
1Department of Earth Sciences, State Key Laboratory of Mineral Deposits Research, Nanjing University, Nanjing, China
2Department of Earth Sciences, Orleans University, Orleans, France

Tóm tắt

The authors select different grain size samples from granitic body in Weishan, central Hunan, to conduct mylonitization experiments under high temperature (HT) and high pressure (HP), by which the temperature and pressure conditions of mylonitization and microstructures of deformation have been obtained. Through the transmission electron microscopy (TEM) observations of experimental mylonite, we calculate its dislocation density (D), differential rheological stress (Pd) and speed rate of strain (Rs): 3.20x109/cm2, 139.32 MPa and 6.39x10-10/s respectively. The results are in the same magnitude-order with those of natural mylonite from fault zones. By comparison and analysis of chemical compositions and microstructures of different structural environments, the authors establish approximate rheological parameters related to shallow structural level and also suggest the multiple rheological properties and total trend from deep structural level to shallow structural level.

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