Crustal Architecture and Magmatism of the Campos Rifted Margin: Along‐Strike Variability and Segmentation

Abstract We investigate the crustal architecture and structural domains of the Campos rifted margin in southeastern Brazil, focusing on rifting evolution and segmentation. Based on 2‐D and 3‐D seismic reflection interpretation and potential field modeling, our results reveal an along‐strike variability, in terms of margin architecture and magmatism, that segments the basin into three main sectors from south to north. Through the analysis of seismic reflection profiles, we interpret this lateral variability as a product of lower‐ to upper‐plate alternations and different magmatic inputs. We propose the Southern Campos margin to represent a lower‐plate tectonic setting, where the distal domain is characterized by the formation of the here named Gávea Supradetachment Basin associated with the development of a metamorphic core‐complex. The Central Campos margin is characterized by a massive residual block, representing an upper‐plate setting, with exhumation of different crustal levels in the distal domain. Our analysis suggests that the Central Campos sustained a high magmatic input throughout the rift evolution, supporting the interpretation of Seaward Dipping Reflectors and a magmatic crust in a transitional domain. The Northern Campos margin also represents an upper‐plate setting, but characterized by a progressively delaminated crust. Finally, we compare the Brazilian margin architecture with the conjugate Angola margin, discuss the role of transfer zones in the segmentation and propose along‐strike variations in the volume of magmatism.