Reconstruction of the tectonic terranes in the Myanmar territory Hla Hla Aung Myanmar Earthquake Committee,MES Building,Hlaing University Campus, Hlaing Township, Yangon, Myanmar Email:
[email protected] Abstract Myanmar represents an evolving continent of two crustal formation history consisting of Burma plate and Indochina plate.Western Myanmar, west of Sagaing Fault ( Burma plate ) consist of three distinct lithotectonic entities of a continental fragment, a subduction-related accreted complex and a coastal area. Eaestern Myanmar that is western continuation of Indochina plate is composed of two tectonostratigraphic terranes. Each terrane is fault-bounded. These terranes may have originated in the southern sites in late Mesozoic-early Tertiary time, than the present position during terrane assembling and accretion to the major continent. There are three collisional and accretionary episodes in Myanmar to have become the present configuration of tectonic terranes: Than Lwin(East. Myanmar) ) in the easternmost part of Myanmar, which is a tectonic linkage between Inthanon Zone of West Thailand and ChangningMenglian belt( West Yunnan); (2)Shan Boundary belt in the west edge of Indochina plate; (3) Rakhine-Andaman-Nicober belt at the westernmost part of Myanmar. These accretionary episodes, ended in early Tertiary, have been followed by post-accretionary deformation of strike- slip faulting of Sagaing Fault in Myanmar; West Andaman Fault and Sumatra Fault System in Sumatra; spreading in Andaman back-arc basin resulting in the break-up of the northern part of Burma Plate (Myanmar) from that of Sumatra and disperse northward along Sagaing Fault since Neogene.There is lack of paleomagnetic data for terranes of Myanmar.Biostratigraphic correlation between known distribution of dorminant Mesozoic representatives of Monotis, Halobia, and Daonella fauna and microfossil assemblages of Tertiary age from Myanmar with those from neighboring countries of SE Asia are made to get estimated paleogeographic position and reconstruction of tectonic terranes for Myanmar. Key words: terrane, accretion, dispersion, fossil,collision , tectonic, correlation, paleogeographic reconstruction
