Spacing of consecutive normal faulting in the lithosphere: A dynamic model for rift axis jumping (Tyrrhenian Sea)

We propose that the flexure of a broken elastic plate can determine the spacing of consecutive and localized zones of shearing on a lithospheric scale. The model provides a dynamic explanation for rift axis migration and, as a consequence, for a ‘wide rift’ mode of extension. Calculated values for rift axis shifting are consistent with the available observations and kinematic modelling results in the Tyrrhenian Basin. The quantitative relation obtained between lithospheric fault spacing and the effective elastic thickness (Te) of the lithosphere can be used in an inverse modelling approach, in which paleo Te values are calculated for a basin where the diachronous and spaced nature of rifting is known.