Gravity anomalies, seismicity, subducting slab folding and surface deformations in the orogenic belts—an example from the Andaman-Nicobar region

Abstract

Geophysical data in relation to the geometry associated with the Andaman-Nicobar arc are less strongly constrained. The lithosphere, after buckling, becomes convex downwards in a series of plunging ridges (anticlines) and depressions (synclines). The variation of tectonic activity is greater in front of the subducting folded oceanic lithosphere whereas volcanoes are confined to the shear zones present over the common limbs of plunging ridges and depressions. The representation of the subducting slab geometry over the surface leads to tectonic variations in the orogenic belts.