The Rio Grande Rise and Jean Charcot Seamount Chain - microcontinents or the trail of the Tristan-Gough hotspot?

Third party funded individual grant

Project Details

Project leader:
Prof. Dr. Karsten Haase

Contributing FAU Organisations:
Lehrstuhl für Endogene Geodynamik

Funding source: Deutsche Forschungsgemeinschaft (DFG)
Acronym: RIOGRANDE - MSM82
Start date: 01/03/2019
End date: 30/04/2019

Abstract (technical / expert description):

The Rio Grande Rise (RGR) is a massive plateau and seamount province in the SW Atlantic that has been assumed to represent a large igneous province formed by voluminous magmatic activity of the Tristan-Gough mantle plume on the South American plate. But new evidence showing that the RGR might be a sliver of continental crust that was captured, and possibly rifted, at the time of continental breakup, is throwing considerable doubt on a hotspot origin. We propose a combined seismic, geochemical, geo- and thermochronological study of the nature of the deep and shallow RGR basement to test our hypothesis that the RGR is a microcontinent that has been modified by a complex tectonic and magmatic history, including 1000 km long rifts, associated with buoyant plume upwelling and formation of the Jean Charcot Seamount Chain. These data will determine the relative amounts of continental and oceanic crust, age and origin of the volcanic rocks, and chemical changes with time. The results will have important implications for the understanding of continental rifting and opening of ocean basins and the role of microcontinents in the formation of hotspot trails.

External Partners

Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung (AWI)
GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel

Last updated on 2019-30-07 at 20:32