Characterisation and evolution of the Mergui Faults in the Tanintharyi Shelf, Andaman Sea Basin

The Andaman Sea Basin is a back-arc spreading basin formed by pull-apart, whose tectonic features and evolutionary mechanism in the eastern are essential for understanding the evolution of Andaman Sea Basin. These strike-slip faults in the east part of the Andaman Sea Basin contribute to understanding the kinematics of strike-slip faults within the obliquely subducting plate. This research analyses the stratigraphic structure and tectonic features in the eastern Andaman Sea Basin based on 2D and 3D seismic data combined with published drilling and seismic profile data. We established the seismic stratigraphic sequences in the east of the Andaman Sea region based on the relevant publication. Faults were finely sculpted using automatic 3D seismic horizon pickup and seismic attributes. Two major fault zones were identified which were named the East Mergui Fault and the West Mergui Fault. Subsequently, the evolution model for the fault zones was established depending on the tectonic features and regional tectonic evolution. The results of the study indicate that the evolution of the eastern Andaman fault zone can be divided into three phases: strike-slip-strong stretching phase during Early Miocene, Middle to Late Miocene torsion-slip, and Pliocene to present dextral strike-slip.