sentence: variation of seismicity with depth across the sunda trench subduction zone , low-angle part is the sunda megathrust -- september 2007 sumatra earthquake shown by star the sunda megathrust is a fault that extends approximately 5,500 km ( 3300 mi ) from myanmar ( burma ) in the north , running along the southwestern side of sumatra , to the south of java and bali before terminating near australia .