704. STEINAR FOSLIE 
by the orogenic folding itself, and lateral pressure existed through- 
out the crystallization period. 
/ 
THE RAANA NORITE FIELD (FIGS. I AND 2) 
This eruptive body, to be especially considered here, is situated 
at the south side of the Ofoten Fjord, west of the known ‘harbor 
of Narvik, at 68°20’ latitude. It has recently been closely inves- 
tigated by the author on account of discoveries in the last years of 
extensive but poor deposits of nickeliferous pyrrhotite. 
In the very rugged country with steep mountains rising directly 
from the sea and differences in height of more than 4,000 feet, the 
whole eruptive mass is exceedingly well exposed, and the results of 
differentiation can be followed in all details. 
The norite is injected into a thick series of garnet-mica schists 
with some interstratified layers of marble. The injection is parallel 
to the schistosity and forms a lens-shaped body with a thickness 
of about 3,500 m. and a diameter of about 12km. ‘The relative 
thickness of the lens is greater than is generally the case in this 
sort of intrusions, and is supposed to be due to the influence of 
some E.—W. folding axes. The section of the eruptive body with 
the present surface has an area of 67 km.?, 3 km.? of which has been 
cut off by erosion. No offsets or crossing dikes occur in the 
surrounding schists. 
The very first investigation teaches that the norite field is not 
homogeneous throughout, but is composed of a central mass of 
quartz-norite and a very considerable and continuous marginal zone 
of more femic normal norite, occupying the border against the 
schist all around the field to a width of one-third to one-fourth of 
the whole diameter. 
To understand the reason for this, it is important to know the 
tectonic position of the eruptive mass. One might of course be 
tempted to believe that the field after differentiation might have 
been thrown down in an inverted fold, and that the basic border 
zone accordingly should represent the lower part of the magma 
basin, separated out by gravitative differentiation in the same way 
as is the case in the Sudbury field. This, however, is definitely 
