Abstract

• The study area is situated along the dextral Sagaing Fault zone, about 208 km long, between Indaw Township in Sagaing Region and Singu Township in Mandalay Region, in central Myanmar. It is demarcated by Latitude 22° 30′ N to 24° 20′ N and Longitude 95° 50′ E to 96° 10′ E. In this area, on the basis of the right stepover (releasing step) pattern; the Sagaing Fault can be subdivided into two segments – the northern Indaw-Peinnegon segment (52 km+) and the southern Peinnegon-Singu segment (156 km). There are four types of structural deformation which are determined from both the mesoscopic and microscopic characters of the oriented samples. These are ductile extensional deformation, brittle-ductile extensional deformation, semibrittle extensional deformation, and brittle extensional deformation. The former three types are especially present in the metamorphic rocks exposed between Chaunggyi and Thabeikkyin, and Katha. The brittle extensional deformation is especially present in the sandstones and conglomerates of Male Formation, Irrawaddy sandstones and Singu basalt along the southern and northern parts of the Sagaing Fault zone in the area. Rock units of the study area show distinctive structural deformation characters related to the progressive deformation processes due to the dextral shearing of the Sagaing Fault.