[S-MP46_28PO1] Deformed rocks, Metamorphic rocks and Tectonics

[SMP46-P18] The stress-strain history of metamorphic sole: the case study of Greece, Turkey, Oman and Andaman islands

*Kenta HOSHINO¹ (1.Shizuoka University, Graduate School of Science)

Keywords:microboudin, metamorphic sole, palaeodifferential stress, Tethys, stress-strain history

Metamorphic sole is formed by intra-oceanic thrusting and is found in some locations around the world. Greece, Turkey, Oman and Andaman islands are Tethys type ophiolite exposured area. The microboudin method, which is palaeostress analysis, is based on the proportion of boudinaged mineral grains with respect to applied differential stress. In this study, we used columnar minerals bearing metacherts from four areas and examined the value of palaeodifferential stress. The microboudin method revealed the value of palaeodifferential stress is 3.3~24.8 MPa and we got stress-strain curve by using strain reversal method. The stress-strain curve indicate the stress history. Palaeodifferencial stress increased until the end of deformation in all samples. This result show that peak P-T condition and peak differencial stress are not simultaneous.