CONCLUSIONS. 365 
eneiss on the east is so sharp as to suggest another fault in the Nugsuak 
peninsula. 
An interesting feature of the geology in the region of Atanikerdluk are 
the dikes. ‘These are not rare along the eastern coast of Disko island 
and on either side of the Vaigat, and more particularly along the north- 
west coast of the outer portion of the Nugsuak peninsula. They appear 
at various angles and without regular trend, but the irregularity is espe- 
cially marked about Atanikerdluk. At the latter point we have, as de- 
scribed by Brown and Nordenskiold, fine examples of crossed and forking 
dikes. The attitude of these, as illustrated by Steenstrup * and by Nor- 
denskiold,y is apparently independent of the position of the sedimentary 
strata or the occurrence of rigid beds. A notable circumstance in this 
connection is the presence of the “‘ burned shales” in the Tertiary from 
1,275 feet to about 1,475 feet above tide on the west side of the large 
ravine.{ The sandstones and shales in contact with the dikes in the 
ravine are, however, slightly altered for a very little distance, but are not 
reddened. There is no subaerial evidence of a dike or other eruptive 
material in contact with the area of reddened hardened shales. 
For some distance eastward from the Atanikerdluk peninsula the 
strand is hemmed by cliffs of the Cretaceous,§ while exposures, probably 
of the older basalts, recur at tide level as a number of reefs off Tokternuk 
-and in the ledges of Ivnarsuit. 
SUMMARY AND CONCLUSIONS 
(1) The Cretaceous and Tertiary rocks in the region described he 
everywhere unconformably upon a hilly basement of old crystallines, 
chiefly gneiss and diorite (Kaersut, Pagtorfik, Ekorfat), or upon early 
Cretaceous or pre-Cretaceous (?) basalts (Niakornat, Alinaitsunguak, Ata- 
nikerdluk). The greatest altitude of the sedimentary terranes is at 
Atanikerdluk, 3,040 feet above sealevel. The old basalts are highly al- 
tered and usually occur as breccias (Niakornat, Alinaitsunguak). 
(2) The prevailing easterly dips of the Lower Cretaceous aleng the 
north side of Nugsuak peninsula, in which the strata should dip west- 
erly, since it is in that direction that the higher and younger beds appear, 
may be in part explained by fault compensation, as illustrated at Ujar- 
artorsuak. A certain degree of irregularity of dip, the variable and often 
* Meddelelser om Grénland, v, frontispiece. Fl. Foss. Arct., vii, frontispiece. 
+ Geol. Mag., vol. ix, 1872, p. 457. 
{ They include Tertiary plant bed no. ii of Steenstrup’s sketches and Heer’s descriptions. 
2 In the large ravine immediately to the east of Atanikerdluk the dip varies from 25° to 35° to the 
northeast, although farther east the edges of the strataseem to indicate less inclination in the 
cliffs along the shore. 
