Intraplate deformation and the Wilson cycle: Insights from the thermo-tectonic basement history from several Gondwana terranes

The Wilson Cycle, a cornerstone of plate tectonic theory, describes the cyclical evolution of ocean basins, from their formation through rifting and spreading, to their eventual closure via subduction and continental collision. While this model has significantly advanced our understanding of tectonic processes along plate boundaries, it remains limited in addressing the dynamics of intraplate deformation. This study revisits the Wilson Cycle by examining the interplay between inherited geological structures, intraplate deformation, and the partitioning of tectonic activity. Using low-temperature thermochronology, specifically apatite fission-track analysis, we investigate the timing, magnitude, and controls of deformation across the (Pre)Cambrian terranes of Southeast Brazil, Southeast Colombia, and Peninsular India, regions traditionally considered stable since their assembly within Gondwana.

In Southeast Brazil, the study integrates results from three key areas: the Brasília Orogen, the São Francisco Craton (SFC), and the Araçuaí Orogen. The findings reveal three major phases of exhumation: (i) the Paleozoic, linked to reactivations in the Brasília Orogen and SFC; (ii) the Early Cretaceous to Cenomanian, in the Araçuaí Orogen; and (iii) the Late Cretaceous to Paleocene, with widespread reactivation across all domains. These results highlight contrasting tectonic behaviors: the SFC concentrated deformation within narrow weak zones, the Brasília Orogen displayed lithospheric rigidity and stability, while the Araçuaí Orogen experienced extensive reactivation, particularly during (post-)rift phases associated with the opening of the South Atlantic.

In the Amazonian Craton in Southeast Colombia, AFT data reveal a rapid basement cooling event during the early Cretaceous, driven by extensional tectonics associated with a back-arc setting. This extensional regime facilitated basement uplift, erosion, and exhumation, followed by a shift to contractional Andean tectonics in the late Cretaceous, which slowed cooling rates.

In Peninsular India, a comparison of the eastern and western passive margins underscores the role of cratonic inheritance in tectonic reactivation. Along the eastern margin, the Dharwar Craton underwent significant exhumation during the Late Jurassic to Early Cretaceous, driven by Gondwana’s breakup, whereas the western margin, with its thicker lithosphere, exhibited subdued deformation. Eastward tilting of the Indian plate during the Cenozoic, combined with Bengal Fan sedimentation, further influenced fault reactivation and intraplate exhumation along the eastern margin.

This study underscores that neither cratons nor orogens conform to a single tectonic behavior, revealing significant variability in their responses to geological processes. While some cratons, such as the Amazon and Dharwar cratons, demonstrate unexpected tectonic activity and exhumation driven by extensional tectonics, others, like the São Francisco Craton, exhibit localized reactivations along weak zones but remain largely stable. Similarly, orogens can follow distinct evolutionary paths: some, like the Brasília Orogen, become resistant to further deformation, effectively stagnating the Wilson Cycle, while others, such as the Araçuaí Orogen, experience reactivation, even far from ancient suture zones, enabling renewed tectonic activity. These examples challenge the traditional Wilson Cycle, demonstrating that intraplate deformation, influenced by lithospheric inheritance, plays a critical role in sustaining or altering the cycle. By integrating these insights, this study contributes to an updated framework for the Wilson Cycle that incorporates the complexities of intraplate deformation.