Original Research ARTICLE
Gravity and magnetic constraints on the crustal structure of the Ceará Plateau, Brazilian Equatorial Margin
- 1Oceanographic Institute, University of São Paulo, Brazil
- 2Institute of Astronomy, Geophysics and Atmospheric Sciences, University of São Paulo, Brazil
The Brazilian Equatorial Margin is a transform passive margin with long fracture zones and several seamounts, including the largest one, the Ceará Plateau. This is a complex and poorly recognized area, with few available geophysical data. Gravity and magnetic data from the Equant I Project, seismic published lines and other previous studies are used to make several models and analyses. We recognized gravity and magnetic anomalies related to a denser, magnetized basement, internally comprised of two magmatic highs. Through gravity and magnetic forward modeling, we estimated the basement surface between 800 and 6000 m and the Mohorovičić discontinuity about 22-23 km below the Ceará Plateau. We also present and discuss the position of the continent-ocean boundary 40 km away from the continental shelf, placing the plateau at the oceanic crust domain, and the area of the transitional crust, with an extension of 40-50 km, formed during the rifting phase of the Atlantic Ocean opening.
Keywords: Ceará Plateau, Brazilian equatorial margin, gravity modeling, Magnetic modeling, Crustal structure
Received: 01 Aug 2019;
Accepted: 06 Nov 2019.
Copyright: © 2019 Moura, Molina, Marangoni and Jovane. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Ms. Denise S. Moura, Oceanographic Institute, University of São Paulo, São Paulo, 05508, São Paulo, Brazil, email@example.com