Crustal fault reactivation facilitating lithospheric folding/buckling in the central Indian Ocean

Abstract

High-quality, normal-incidence seismic reflection data confirm that tectonic deformation in the central Indian Ocean occurs at two spatial scales: whole lithosphere folding with wavelengths varying between 100 and 300 km, and compressional reactivation of crustal faults with a characteristic spacing of c. 5 km. Faults penetrate through the crust and probably into the upper mantle. Both types of deformation are driven by regional large intraplate stresses originating from the Indo-Eurasian collision. Numerical modelling of the spatial and temporal relationships between these two modes of deformations shows that, in agreement with geophysical observations, crustal faults are reactivated first with stick-slip behaviour. Subsequent lithospheric folding does not start until horizontal loading has significantly reduced the mechanical strength of the lithosphere, as predicted by elasto-plastic buckling theory. Modelling suggests that lithospheric folding does not develop in the absence of fault reactivation. Crustal fault reactivation, therefore, appears to be a key facilitating mechanism for oceanic lithospheric buckling in the central Indian Ocean.

Spectral analysis of the gravity and elevation along the western Africa–Eurasia plate tectonic limit: Continental versus oceanic lithospheric folding signals

“…Numerical modelling of lithospheric folding is generally undertaken using thermo-mechanical models along 2D vertical cross sections (McAdoo and Sandwell, 1985;Beekman et al, 1996;Burov and Cloetingh, 1997;Burov and Poliakov, 2001;Cloetingh et al, 2002;Schmalholz et al, 2009), as well as with plain strain models that incorporate the elastic deformation of the lithosphere and processes of erosion and sedimentation with the development of drainage systems (García-Castellanos, 2002). More recent experiments on these types of structures are using lithospheric-scale analogue models (Martinod and Davy, 1994;Sokoutis et al, 2005;Luth et al, 2010;Fernández-Lozano et al, in press).…”

Post-rift compressional reactivation potential of passive margins and extensional basins

“…Numerical models have been developed for the simulation of the interplay of faulting and folding in intraplate compressional deformation (Beekman et al 1996;Cloetingh et al 1999;Gerbault et al 1999). Models have also been developed to investigate the effects of faulting on stress-induced intraplate deformation in rifted margin settings .…”

Destruction of the North China Craton: Lithosphere folding-induced removal of lithospheric mantle?

“…Lithosphere folding has been recognized in the cratonic lithospheres of central Australia (Lambeck, 1983;Stephenson and Lambeck, 1985;Goleby et al, 1989;Beekman et al, 1996), central Asia Burov et al, 1993;Burg et al, 1994), Arctic Canada (Stephenson et al, 1990), and Europe (Lefort and Agarwal, 1996;Waltham et al, 2000;Cloetingh et al, 2002). Cloetingh et al (1999) have provided a summary.…”