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intrusion along regular fractures. In these periods the alaskite, andesite,
and granophyre dykes were formed. The relation of the alaskite to the
andesite and granophyre was not observed, but on the basis of its chemical
and mineralogical similarity to the leucogranite, pegmatite, and graphic
granite, the alaskite is believed to be closely connected with the sequence
of granitization and pegmatite formation. The alaskite could represent
a late-stage up-welling of granitic material similar to that which had
given rise to, or perhaps which had been produced at depth by, the
granitizing and pegmatite-forming solutions.

(5) The andesite dykes were emplaced. These rocks have been
observed to cut all of the rock types of the Wolverine complex except
the alaskite, and are themselves cut by the granophyre porphyry. The
andesite dykes observed are found in long straight fractures that appear
to be due to regional, rather than local, deformation. Somewhat similar
dykes are found in much younger, less metamorphosed rocks in several
places within the map-area; consequently, they are not considered as
products of the peculiar processes that produced the ‘Wolverine complex’.

(6) The stocks and dykes of granophyre porphyry were formed. These
rocks are younger than the andesite dykes, and like them, their presence
within the area of Wolverine complex rocks appears to be fortuitous.

AGE OF THE GRANITIZING ACTIVITY

There is little definite evidence regarding the time of operation of the
processes producing the Wolverine complex rocks. The process has affected
Ingenika group strata, and is thus post-Lower Cambrian. Apparently, it
occurred later than the regional metamorphism, and almost certainly later
than at least one episode of folding (post-Lower Cambrian, pre-Mississip-
pian) of the Ingenika group rocks.

The dominant period of igneous activity in north-central British
Columbia is represented by the Omineca intrusions, which are associated
with orogenic activity extending from late Jurassic through most of
Cretaceous time. However, in no place are these intrusions known to
have produced metamorphic effects similar to the effects of the processes
that produced the Wolverine complex, and there does not seem to be any
evidence on which this complex and the Omineca intrusions could be
inferred to be genetically connected (Armstrong, in Gilluly, 1948, p. 123;
and Armstrong, 1949, p. 28). The fact that the processes producing the
Wolverine complex are not known to have affected Mississippian and
younger rocks suggests that they may have ceased operation before
the Mississippian rocks were laid down. A bed of conglomerate in the
rock assemblage containing strata of Mississippian to probably Permian
age, exposed in the Lay Range 24 miles northwest of Blackpine Lake,
contains boulders of grey granodiorite mineralogically and texturally
similar to the granodiorite of the Wolverine complex, in a matrix made
up largely of fragments of quartzite, some of which are feldspathic,
micaceous, and gneissic (See page 115). This conglomerate suggests
that granitic and high-grade metamorphic rocks had formed, and had been
exposed by erosion, by late Paleozoic time. The granitizing activity
producing the Wolverine complex rocks thus seemingly occurred in post-
Lower Cambrian, probably pre-Mississippian, time.