Mobility of South America's transcontinental drainage divide and shrinkage of the Parana river basin linked to lithologic and geodynamic controls.

ABSTRACT: The South American Transcontinental Drainage Divide (TDD) is roughly oriented NE-SW from its Atlantic termination in SE Brazil to its NW termination in the limits between the southwestern edges of the Amazon Craton and the Andean Foreland. Based on a weak spatial coincidence with 90 - 70 Ma igneous intrusions, the origin and stability of the TDD have been attributed to intraplate magmatic activity. Using geomorphic analysis of drainage divides, we infer an overall southward migration of the TDD, even in areas with constrained uplift associated with intrusions. Most of the TDD is also the main drainage divide of the Paraná River Basin (PRB). Our analysis of the PRB divides reveals wholesale basin shrinkage, consistent with the southward migration of the TDD. We infer that the basalts of the

SUBMITTER: Crelier C 

PROVIDER: S-EPMC11761504 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature