Earth structure South America 6 Structural geology 6 Argentina 4 Basalt 4 Circular structures 4 Geophysics 4 Gravity anomalies and Earth structure 4 Late Pliocene 4 Olivine basalts 4 basalt 4 conglomerate 4 data interpretation 4 gravity anomaly 4 magnetic anomaly 4 meteorite 4 olivine 4 topography 4 2.5D magnetic modeling 2 Analytic signals 2 Andes 2 Apparent electrical conductivity 2 Atlantic Ocean 2 Chubut 2 Circular pattern 2 Continental margin 2 Continental margins: convergent 2 Cratons 2 Data processing 2 Debris 2