Crustal Magnetization Model of Maud Rise in the Southwest Indian Ocean

We modeled the crustal magnetization for the Maud Rise in the south-west Indian Ocean off the coast of East Antarctica using magnetic observations from the Oersted satellite and near-surface surveys complied by the Antarctic Digital Magnetic Anomaly Project (ADMAP). A new inversion modeling scheme of the multi-altitude anomaly fields suggests that the magnetic effects due to crustal thickness variations and remanence involving the normal polarity Cretaceous Quiet Zone (KQZ) become increasingly dominant with altitude. The magnetic crustal thickness effects were modeled in the Oersted data using crustal thickness variations derived from satellite altitude gravity data. Remanent magnetization modeling of the residual Oersted and near-surface magnetic anomalies supports extending the KQZ eastwards to the Astrid Ridge. The remaining near-surface anomalies involve crustal features with relatively high frequency effects that are strongly attenuated at satellite altitudes. The crustal modeling can be extended by the satellite magnetic anomalies across the Indian Ocean Ridge for insight on the crustal properties of the conjugate Agulhas Plateau. The modeling supports the Jurassic reconstruction of Gondwana when the African Limpopo-Zambezi and East Antarctic Princess Astrid coasts were connected as part of a relatively demagnetized crustal block.