Abstract
The Ilimaussaq intrusion belongs to the late Precambrian Gardar province of South Greenland (fig. 1). The province ean be regarded as a cratogenic rift province with similarities to the East African rift system and the Oslo igneous provinee (Upton, 1974; Emeleus & Upton, 1976). The provinee consists of continental sandstones, and a variety of volcanic and plutonic igneous rocks many of which are alkaline. An important series of faults have influenced the position of the plutonic centres and presumably facilitated the rise of magma into the upper erust. The alkaline roeks evolved towards Si-rich melts such as comendites and alkali granites, and towards Si-poar melts such as phonolites and nepheline syenites. Both types of evolution are present at Ilimaussaq (fig. 2).
Highlights
The IHmaussaq intrusion belongs to the late Precambrian Gardar provinee of South Greenland
Geological and geochemical evidence suggests that the intrusion was emplaced in three main pulses - augite syenite, acid rocks, and agpaitic rocks
The augite syenite has been regarded by many authors as representative of the parent magma for the Ilimaussaq intrusion, but recent work suggests it is largely cumulitic
Summary
The IHmaussaq intrusion belongs to the late Precambrian Gardar provinee of South Greenland (fig. 1). The IHmaussaq intrusion belongs to the late Precambrian Gardar provinee of South Greenland The provinee consists of continental sandstones, and a variety of vo1canic and plutonic igneous rocks many of which are alkaline. The alkaline roeks evolved towards Si-rich melts such as comendites and alkali granites, and towards Si-poar melts such as phonolites and nepheline syenites. Both types of evolution are present at IHmaussaq The position of the intrusion, and its steep margins, suggest that the intrusion was largely emplaced by block subsidenee (Sørensen, 1978; Nielsen & Steenfelt, 1979) into a Preeambrian granite basement and the overlying Gardar sandstones and lavas. In the roof zone there are local signs of piecemeal stoping and the final nepheline syenites (1ujavrites) intruded nearby country rocks in a few places
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
