68 
a result of this the sodalite-foyaite forms the surface of the 
ground over nearly the whole stretch from Tupersuatsiak to 
Nunasarnausak, whereas down towards Kangerdluarsuk the nau- 
jaite lies exposed on the slopes of the mountain. From Tu- 
persuatsiak towards the east the transitional zone rises somewhat 
more rapidly; already a short distance to the east of Tuper- 
suatsiak it is met with at a height of 150 meters and a little fur- 
ther to the east the naujaite forms the surface of the plateau, 
the sodalite-foyaite having been removed by erosion. 
Taken as a whole the sodalite-foyaite thus forms a thick 
sheet or stratum which rests upon the naujaite. At places the 
thickness is considerably over 150 meters. The sheet is not 
Agpat Tupersuatsiak Naujakasık о 
WISN 
Lujavrite Sodalite-foyaite | Lujavrile 
LT Sandstone ele 
oem Damen & Nawjaite ae 
Fig. 11. Schematic section along the southern coast of Tunugdliarfik, from 
Agpat to S. Siorarsuit: showing stratiform arrangement of the different 
varieties of nepheline-syenite. — Length of section about 10 kilometers. 
quite horizontal, but forms a flat basin with the lowest part 
lying close to the west of Tupersuatsiak and rising from there 
to the east, south and west (Fig. 11). The district south of the 
Tunugdliarfik Fjord contains only the southern half of the basin; 
the remainder is found in the mountains north of the fjord. 
The earlier mentioned, oldest pegmatite sheets of the naujaite 
as well as the very distinct system of parting, run parallel with 
the under-surface of the sodalite-foyaite, and the same is the 
case with the lujavrite veins in the deeper part of the naujaite. 
Thus the nepheline-syenites constitute a stratified igneous com- 
plex which is built up of a number of slightly concave sheets, 
the one above the other (cf. also the figures pp. 38 and 61). 
Transitional forms covering the sodalite-foyaite. — At a 
few places within the district considered here the sodalite-foyaite 
