The Kohnen Lineament – a prominent magnetic anomaly pattern in southern Dronning Maud Land, East Antarctica
The Pan-African (650-500 Ma) collision of East- and West Gondwana affected a major part of the Dronning Maud Land. The western front of this collision zone is exposed at the nunataks of the Heimefrontfjella, where a major shear zone separates Pan-African metamorphic overprinted rocks in the east from non-overprinted rocks in the west. The shear zone causes an elongated magnetic anomaly, which allows tracing the shear zone into the ice-covered areas NE and SW of the Heimefrontfjella. A similar elongated magnetic anomaly has been detected 300 km farther east close to the Kohnen Station, named Kohnen lineament. The anomaly stretches out from NE to SW over a distance of about 100 km. In the NE it links to the Forster Magnetic Anomaly, whereas it passes into another narrow and stretched anomaly in the SE, indicating a possible continuation. However the causing geological structures are inaccessible for direct geological sampling, as the area is completely covered by ~3 km thick ice, but the aeromagnetic data indicate that the Kohnen Lineament could represent the eastern front of the East-West Gondwana collision zone in this region.