Thermal history, exhumation, uplift, and long-term landscape evolution of the western south Atlantic passive continental margin, Brazil and Namibia-Angola

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The aim of the project is to quantify the temperature, exhumation, uplift, and long-term dynamic topography evolution of the South Atlantic passive continental margin (SAPCM) in Brazil and Namibia-Angola. Excellent onshore outcrop conditions and complete rift to post-rift archives between Sao Paulo and Porto Alegre and in the transition from Namibia to Angola (onshore Walvis ridge) allow a high precision quantification of long-term processes and process-response systems. We will integrate the published thermochronological data from Brazil and Namibia. This climate-continental margin-mantle coupled process-response system is caused by the interaction between endogenic and exogenic forces, which are related to the mantle-process driven rift – drift – “passive” continental margin evolution of the South Atlantic, and the climate change since the Early/Late Cretaceous climate maximum. Special emphasis will be given to the influence of long-living transform faults such as the Florianopolis Fracture Zone (FFZ) on the long-term dynamic topography evolution of the SAPCM s. A combination of apatite and zircon fission-track and (U-Th)/He thermochronological data with modeling of t-T path´s will determine the thermal, exhumation, and uplift history. A long-term landscape evolution model with process rates will be achieved by thermo-kinematic 3-D modeling (software code PECUBE). Testing model solutions obtained for a multidimensional parameter space against the real thermochronological and geomorphological data set, the most likely combinations of parameter rates, and values can be constrained. The data and models will allow to separate the exogenic and endogenic forces and their process rates. In a continuation of the research (2013-2016), strong emphasis will be given to the integration of all existing and published data (including those data of other SPP-research projects) in a numerical model for the long-term landscape evolution to quantify the surface response rates.