Geophysical characterization of two circular structures at Bajada del Diablo (Patagonia, Argentina): Indication of impact origin

► Almost 200 circular structures exist in basalts and conglomerates in Patagonia, Argentina. ► New magnetic and electromagnetic surveys help constrain the origin of these structures. ► Magnetic anomalies and higher conductivity exist around the structure rims. ► These anomalies are associated with accumulations of basalt clasts. ► Evidence suggests that the circular structures are of extra-terrestrial impact origin.