We use the Bouguer coherence (Morlet isostatic response function) technique to compute
the spatial variation of effective elastic thickness (T e) of the Andaman subduction zone. The
recovered T e map resolves regional-scale features that correlate well with known surface
structures of the subducting Indian plate and the overriding Burma plate. The major structure
on the India plate, the Ninetyeast Ridge (NER), exhibits a weak mechanical strength, which
is consistent with the expected signature of an oceanic ridge of hotspot origin. However, a …