EGU2020-17533
https://doi.org/10.5194/egusphere-egu2020-17533
EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Magnetostratigraphy and environmental magnetism of the Aptian-Albian boundary of sedimentary core from Sergipe-Alagoas Basin: preliminary results

Raquel Gewehr de Mello1, Gerson Fauth2, Karlos Guilherme Diemer Kochhann2, Carolina Gonsalves Leandro1, Mauro Daniel Rodrigues Bruno2, Guilherme Krahl2, Fernando Marcanth Lopes2, and Jairo Francisco Savian1
Raquel Gewehr de Mello et al.
  • 1Universidade Federal do Rio Grande do Sul, Instituto de Geociências, Paleontologia e Estratigrafia, Brazil (raquel.mello@ufrgs.br)
  • 2Universidade do Vale do Rio dos Sinos

The Early Cretaceous was dominated by greenhouse conditions and increases in ocean crust production rate, with critical climate, geography and oceanography changes and abrupt shifts in redox conditions in the oceans. Prior to the Aptian, regarding the Earth’s magnetic field, a high rate of polarity reversals dominated. However, thereafter, a period of polarity stability, known as the Cretaceous Normal Polarity Superchron (CNPS), was established for 34 Myr. Although, there are debates on the causes and consequences of these extreme events. The exact behavior of the geomagnetic field in this period is still poorly understood, and data from volcanic and sedimentary rocks are conflicting. The biostratigraphy data from the sedimentary succession from the Aptian-Albian interval in the Sergipe-Alagoas Basin (Brazil) are rare and correlations are weak with Tethyan realm. Since some of the major reservoirs of the terrestrial portion of the Sergipe-Alagoas basin are from Aptian-Albian ages the lack of age models brings difficulties to the oil industry. Magnetic parameters such as magnetic susceptibility, ARM, IRM, and magnetostratigraphy data were obtained with a resolution of 25 cm in the Core SER-03 from Sergipe-Alagoas Basin. The entire section varies 4 Myr, including the Aptian-Albian boundary. Here, we present preliminary environmental magnetism and magnetostratigraphic interpretation for this core. Therefore, these data will aid to develop an age model framework in order to assist this uncovered region and for future comparisons with Tethyan realm.

How to cite: Gewehr de Mello, R., Fauth, G., Guilherme Diemer Kochhann, K., Gonsalves Leandro, C., Daniel Rodrigues Bruno, M., Krahl, G., Marcanth Lopes, F., and Francisco Savian, J.: Magnetostratigraphy and environmental magnetism of the Aptian-Albian boundary of sedimentary core from Sergipe-Alagoas Basin: preliminary results, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-17533, https://doi.org/10.5194/egusphere-egu2020-17533, 2020