Structural deformation of the Momeik-Myitson area, Momeik Township: criteria for tectonics

The research area is situated within the northern adjacent part of the Momeik Town. It is mainly composed of metamorphic (metapelite, metacarbonate and metaigneous) and associated igneous rocks. The present work deals to describe the petrographic criteria of structural deformation and to interpret the tectonic evolution of the study area. The investigations of numerous deformational criteria observed in various units of the study area point out that the research area might have been encountered four different styles of deformation during Tertiary period. These are (i) E-W compressional deformation (Eocene to Oligocene), (ii) NNW-SSE ductile-extensional deformation (Oligocene to Early Miocene), (iii) brittle-ductile deformation (Early to Middle Miocene), and (iv) brittle-extensional deformation (Middle Miocene). On the basis of the well-documented regional tectonic consideration combined with available field data and petrological interpretation, it might be concluded that the metamorphic rocks of the study area might have been exhumed by the extensional tectonics accompanied with E-W compressional deformation during Middle Miocene