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On the prospecting and geology of the Kemi chromite deposit, Finland 37
thickness. However, it should be added that also within the hanging wall
part of the ore belt there occur oreless andJor chromite-poor zones.
A more detailed exposition of the occurrence of the chromite can be found
in connection with the petrographic description.
The observations made of the dip in the mineralized zone are confined
to the ore belt and the dip of the contact with the albitic rock.
The definition of the dip of the ore belt is based on the connections of the
sections made at different depth levels, in which the contact of the hanging
wall of the ore, by virtue of its continuity, has been determinative. The
dip in the southwestern part of the ore belt has been measured as being
65° NW. In the vicinity of Elijärvi it is possibly a bit steeper in places,
or about 70°, though there, too, the majority of observations give the same
figure of 65°. In the northern part of Elijärvi, after the northern arching
of the ore belt, a single observation indicates a marked grading down
of the dip.
The contact on the surface between the ultrabasic and the albite rock
could be determined quite accurately from the geophysical profile. Connecting
this with the albite rock met with deeper in the drillhole, the dip of
the contact yields a value of approximately 65° NW.
Common throughout the entire metasomatic zone are sheared zones.
Their occurrence is most frequently to be observed along the hanging wall
margin of the ore belt, but they are to be found also at greater distances
from the ore as weIl as within the intercalating zones of oreless rock inside
the ore belt. The ore itself contains no sheared zones, although the adjacent
sheared zones are quite likely to have caused shearing at the edges of the
ore-bearing rock.
THE ORE OCCURRENCES INVESTIGATED
Drilling operations were concentrated in four different areas in the
anomaly zone, these having been interpreted in the light of geophysical
indications to be most promising from the economic standpoint. An ore
occurrence was also discovered in each area, and they were named as
follows:
West End ore (Länsipään malmi),
Nuottijärvi ore,
Elijärvi ore, and
Viianmaa ore.