CHAPTER III. 
DESCRIPTIVE GEOLOGY ОВ 
ILIMAUSAK REGION. 
INTRODUCTORY. 
The region to be described in the present chapter embraces 
the igneous complex of Ilimausak and its surroundings. Its 
situation is shown on the index map, Fig. 2 and a geological 
map on a larger scale (about 1: 113,000) is given on Plate HI’. 
The whole region can be viewed from Mount Ilimausak, which 
lies in the northern part of the district, and whose two highest 
peaks, separated by a small glacier, reach altitudes of respec- 
tively 1370 meters and about 1450 meters. 
The main direction of the four large fjords which cut through 
the region is from west-south-west to east-north-east. The 
southernmost is called Kakortok Fjord and lies entirely within 
the area of the Algonkian granite. The newer igneous rocks 
have their southern boundary a little to the north of the water- 
shed between this fjord and the next one, Kangerdluarsuk, 
1 The topographical foundation of the map has come essentially from the 
surveys made by STEENSTRUP, HOLM, and others, whose maps have been 
published in earlier volumes of the Meddelelser om Grönland. During 
the geological survey of the region in 1900 and 1908 no trigonometrical 
measurements were made, but at several places on the map details from 
sketches and photographs have been added for geological reasons. The 
heights of the hills are given in meters and are also taken for the most 
part from the work of earlier expeditions. The contour-lines are only 
intended to show the orography very roughly; they are drawn mainly 
from the barometric measurements and photographs of 1900. 
