Compression of oceanic lithosphere - An analysis of intraplate deformation in the Central Indian Basin

The development of intraplate structure in the Central Indian Basin is examined using models in which deformation is due to flexural buckling and the hydrodynamic growth of instabilities. Comparison of the models reveal that in a strong viscous lithosphere, deformation of the layer occurs by flexural folding at a wavelength which corresponds to the flexural buckling theory; in a lithosphere of intermediate strength, the layer deforms by folding characterized by thickening which localizes beneath topographic heights; and in a relatively weak lithosphere, the layer incurs an even greater amount of localized thickening and deforms in the symmetric or pinch-and-swell mode by inverse boudinage. It is noted that the models in which the layer folds either flexurally or with periodic thickening correspond with observed depth distribution of seismicity in the Central Indian Basin and with experimental rock rheological data.