Open AccessScientific Drilling in the South Atlantic
Author(s) -
Santos Roberto Ventura,
Glasmacher Ulrich A.,
Geldmacher Jörg
Publication year - 2014
Publication title -
eos, transactions american geophysical union
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.316
H-Index - 86
eISSN - 2324-9250
pISSN - 0096-3941
DOI - 10.1002/2014eo270007
Subject(s) - geology , continental margin , breakup , mantle (geology) , paleontology , igneous rock , rift , continental shelf , drilling , mid atlantic ridge , earth science , ridge , oceanography , tectonics , psychology , mechanical engineering , psychoanalysis , engineering
The South Atlantic is a classic example of continental breakup in which the mechanisms that drove the initial fragmentation still need to be detailed. Mantle plumes may have played a key role in this process, as implied by the Rio Grande Rise (RGR) and Walvis Ridge (WR) hot spot tracks. Their role in the South Atlantic opening is uncertain, as questions remain about their origin and relationship with the structure and dynamics of the upper mantle. Recent findings indicate that the western margin of continental South America did not behave as a rigid block but instead stretched significantly, allowing the emplacement of igneous and exhumed mantle rocks. Continental rifting may have rafted fragments of the continents into the ocean, as implied by recently dredged continental rocks from the RGR.