Análisis de los mapas de anomalías gravimétricas y geomagnéticas de las campañas geofísicas marinas BRAVOSEIS 2019- 2020 (Cuenca Central del Bransfield, Antártida)
- J.L. Granja-Bruña 1
- D. Martín-Jiménez 2
- F. Fernández-Sáez 2
- L. Vizcaíno 2
- T. Teixidó 2
- D. Soule 3
- J. Almendros 2
- W. Wilcock 4
- 1 Univ. Complutense de Madrid
- 2 Univ. de Granada
-
3
Queens College, CUNY
info
- 4 University of Washington, USA
ISSN: 1576-5172
Year of publication: 2021
Issue Title: X Congreso Geológico de España
Issue: 18
Pages: 986
Type: Article
More publications in: Geotemas (Madrid)
Abstract
The Central Bransfield Basin shows a chain of submerged volcanic edifices developed along an active segmented back-arc spreading center. Into the BRAVOSEIS (CTM2016-77315-R) amphibious project, in 2019 and 2020, two marine geophysi- cal cruises were carried out onboard the R/V Sarmiento de Gamboa and Hesperides, respectively (Almendros et al., 2020). Data acquisition consisted in 2D MCS seismic, grav-mag, high-res seismic and swath bathymetry data. Complete Bouguer (BC) and Reduced-to-Pole (RTP) anomalies are different between the volcanic edifices of Orca and Humpback. CB anomaly differences could be partially attributed to variations in crustal thickness. In this sense, the crust in the Humpback is thic- ker because of less amount of backarc extension. Positive RTP anomalies define a sinuous elongated maximum along the neovolcanic rift. Maximum RTP anomalies are centered over the Orca caldera but in the case of the Humpback edifice they are located along the ridge cross-cutting the caldera. These different RTP anomalies could be attributed to distinct stages of fissure and caldera volcanism. High-resolution anomaly maps allow to associate local anomalies to smaller structures along the neovolcanic zone. Future works will integrate regional datasets, and 2D/3D grav-mag modeling constrained with seismic data.