94 
Narsak is a pleasant little hamlet, situated at the western 
foot of Kakarsuak on a small plain covered with vegetation; 
it is one of the few places in Greenland where cows can be 
kept. Owing to the alluvial deposits and vegetation which con- 
ceal the rocks, the geological investigations are more difficult 
here than at the places mentioned hitherto. In addition, the 
geological structure is extremely complicated and the following 
description can therefore only be regarded as an account of the 
most conspicuous features. 
BASEMENT GRANITE 
AND SANDSTONE AT NUGARSUK. 
Nugarsuk is the name of the low peninsula about two 
kilometers south-east of Narsak. The rock furthest out on the 
peninsula is Algonkian granite (Julianehaab granite) of a white 
or reddish-gray colour. In the northern part of the peninsula 
the granite is covered by arkose, and this in turn by the sand- 
stone; the lowermost sandstone-beds are of a red colour but 
the upper beds are white and quartzitic. The bedding planes 
have a slight inclination towards the north or north-west. The 
main features of the geological structure are thus similar to 
those on the south coast of Tunugdliarfik Fjord (p. 62), but the 
arkose at Nugarsuk shows a much greater development. 
The rocks are best exposed on the small peninsula close 
to the north-west of Nugarsuk. Here the arkose covering the 
granite has a thickness of 10—15 meters; it is very compact 
and on a cursory view may be mistaken for granite. The 
lowermost portions of the arkose are of a greenish-white colour, 
the main body brownish-red. It consists of large and small 
grains of quartz and felspar, intermingled with a microcrystal- 
linic aggregate of felspar and epidote, which seems to have 
originated by conversion of the original felspar. ‘The quartz is 
frequently of a milky appearance and the felspar is not very 
fresh. The red varieties of the arkose are filled with minute 
