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Most of South Greenland (south of 62oN) was covered by the Aeromag 1995 survey.
The main geological units in the survey area are the Archean craton to the north and the Palaeoproterozoic Ketilidian orogen to the south. The Aeromag 1995 project covers most of the Ketilidian mobile belt and the boundary to the older Archean rocks to the north. The boundary between the two regions is at the west coast placed near 61o30'; north of this is what is usually referred to as 'the border zone'. A part of the Archean craton is to varying degrees overlain by the Ketilidian supracrustal rocks and influenced by tectonic events and the later Midproterozoic Gardar events.
The Archean craton of Greenland is the largest and best exposed craton of the North Atlantic cratons. It consists mainly of granitoid quatzo-feldspathic gneisses, probably largely derived from acid to intermediate igneous rocks, but encompasses also rafts of amphibolites. There are many occurrences of supracrustal rocks of varying age within the surveyed area. Most of the craton experienced serveral phases of folding, faulting and/or metamorphism, often in granulite facies.
The Palaeoproterozoic Ketilidian orogenic belt can be divided into four zones: the Border zone, the Julianehåb batholith, the Psammite Zone and the Pelite Zone.
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