“…To date, many studies have been made to investigate the structure and tectonics of SE Asia through various approaches such as geodetic measurements (Hinschberger et al, 2005;S. Zhao et al, 2023), geological surveys (Earle, 2023;Harris, 2006), and seismological investigations (Hua et al, 2023;Richards et al, 2007). However, there are two contrasting hypotheses about the cause of the curved arc: two different slabs subducting toward each other (Cardwell & Isacks, 1978;Das, 2004) or folding of one single slab (Pownall et al, 2016;Spakman & Hall, 2010).…”