2014/05/19 by A. Bronner, Daniel Sauter, Marc Munschy +4 · 1 citation
Biochemistry, Genetics and Molecular Biology · Earth and Planetary Sciences · #Geomagnetism and Paleomagnetism Studies #Geological and Geochemical Analysis #High-pressure geophysics and materials #Geology #Seafloor spreading #Magnetic anomaly #Mantle (geology) #Volcano #Mid-ocean ridge #Geophysics #Ridge #Seismology #Geochemistry #Paleontology
paper · pdf · doi:10.5194/se-5-339-2014
openalex publication_date 2014/05/19 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/22
Abstract. We investigate the magnetic signature of ultramafic seafloor in the eastern part of the Southwest Indian Ridge (SWIR). There, detachment faulting, continuous over 11 Myr, exhumed large areas of mantle-derived rocks. These exhumed mantle domains occur in the form of a smooth rounded topography with broad ridges locally covered by a thin highly discontinuous volcanic carapace. We present high-resolution data combining deep-tow magnetics, side-scan sonar images and dredged samples collected within two exhumed mantle domains between 62° E and 65° E. We show that, despite an ultra-slow spreading rate, volcanic areas within robust magmatic segments are characterized by well-defined seafloor spreading anomalies. By contrast, the exhumed mantle domains, including a few thin volcanic patches, reveal a weak and highly variable magnetic pattern. The analysis of the magnetic properties of the dredged samples and careful comparison between the nature of the seafloor, the deep-tow magnetic anomalies and the seafloor equivalent magnetization suggest that the serpentinized peridotites do not carry a sufficiently stable remanent magnetization to produce seafloor spreading magnetic anomalies in exhumed mantle domains.