Modeling Lithospheric Thickness Along the Conjugate South Atlantic Passive Margins Implies Asymmetric Rift Initiation

The lithospheric architecture of passive margins is crucial for understanding the tectonic processes that caused breakup Gondwana. We highlight evolution South Atlantic by a simple thermal lithosphere-asthenosphere boundary (LAB) model based on onset and cessation rifting, crustal thickness, stretching factors. simulate thinning select LAB as T = 1,330°C isotherm, which calculated 1D advection diffusion. Stretching factors margin geometry are adjusted to state-of-the-art data sets, giving especially designed continental Atlantic. Our shows distinct variations along not imaged global models, indicating different rifting mechanisms. For example, we up 200 km deep lithosphere in American Santos Basin shallow less than 60 Namibe offshore Africa. These two conjugate basins reflect strong asymmetry depth resembles width. In Gondwana reconstruction, discuss these patterns together with seismic velocity perturbations Central Austral Segments margins. correlates signatures Angola Dome, attributed epeirogenic uplift Neogene, suggesting an additional component post-breakup thinning.