A study of volcanic rocks and ferromanganese crusts through marine geophysical methods integration in the north portion of Cruzeiro do Sul Rift in the Rio Grande Rise

The Rio Grande Rise (RGR) is an extensive structural high located in the South Atlantic Ocean, target of increasing exploratory interest. During last decades, considerable attention has been given to its genesis, dynamic, regional tectonic, and composition. Some studies indicate presence volcanic rocks, mainly basaltic, related their origin Ferromanganese Crusts, boosting research economic This study suggests location rocks FeMn crusts at north portion Cruzeiro do Sul Rift within RGR, characterizing local geology distribution pattern. We used multibeam bathymetry, sidescan sonar, dredges, magnetic field data integrate better constrain results. highlighted probable basaltic agreeing with published literature, which was afterward confirmed by dredge samples. Their anomalies displayed predominance reverse polarization less frequent normal anomalies. need a large volume magnetite cause field, does not happen RGR. There, they have reduced thickness are frequently eroded, as geological data. Magnetic lineaments margin defined zone series faults. formation, transcurrent movements caused intense fracturing, providing pathways for magma intrusion. Therefore, fault could be primary function intrusion occurrence rifting process seafloor spreading. new presented this paper brings valuable comprehension exploration effort