Kialineq

The Kialineq centre extends over about 30x10 km and comprises a number of quartz syenite and granite plutons, emplacement of which was by cauldron subsidence with the formation of ring dykes (Brown and Becker, 1986). To the south of these intrusions lies the earlier Imilik gabbro which is layered throughout (Deer, 1976, Fig. 359). Associated with the felsic intrusions is an extensive complex of mixed acid and basic rocks with apparent chilling of basic against acid, basic pillow structures and net-veining. The main quartz syenites are generally variable in composition but typically comprise perthite, a little interstitial quartz, ferrohedenbergitic to ferroaugitic pyroxenes partly replaced by amphibole, fayalite and biotite; ferrohornblende is the principal mafic mineral in some areas and rare chevkinite is found. Less abundant but more alkaline varieties of syenite contain pyroxene zoned to aegirine-augite rims and surrounded by alkali amphibole; aenigmatite may be present. The principal granite has biotite as the sole mafic mineral. A small area of volcanic rocks has been preserved by down faulting in one area, and includes peralkaline rhyolites. Analyses of rocks and a range of minerals will be found in Brown and Becker (1986), Brown et al. (1877) and Deer (1976).