The First Data on the Composition of Rocks of the Atlantis Rise (Central Atlantic)

Resumo

New data on the composition of volcanic rocks of the Atlantis Rise (Central Atlantic) have been obtained. Incoherent element ratios suggest that those volcanics were formed at low degrees of partial melting within a garnet facies at depth. The isotopic ratios of Pb and Nd imply that their compositions cannot be unequivocally attributed to any of the nearby magmatic provinces (Madeira, Canary, or Cabo Verde). They are distinguished by high radiogenic Pb isotopes, indicating a significant addition of a HIMU component. No significant EM1 addition has been observed. It may be assumed that the Atlantis Rise volcanics were formed from an independent mantle source.