Buckling of the oceanic lithosphere from geophysical data and experiments

Two major hypotheses have been advanced for the formation of the long wavelength (100–300 km) undulations of oceanic basement and overlying sediments developed in the central Indian Ocean basin: whole layer folding (buckling) and local thickening (inverse boudinage). Using appropriately scaled two‐layer analogue models for the oceanic lithosphere comprising a brittle layer above a ductile layer, we show that buckling of the entire brittle layer is likely to be the mode of deformation. However, the lithosphere‐asthenosphere boundary remains undisturbed. We find a relationship between the thickness of the brittle layer and the wavelength of folding such that the wavelength is 7 times the brittle layer thickness.