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tions are represented, from recognizable sedimentary strata that have
suffered low- to medium-grade regional metamorphism, to high-grade
gneisses, migmatites, and rocks of granitic aspect. It is also apparent that
the intensity of the “additional” metamorphism and replacement increases
progressively toward a centre now represented by the grey granodiorite
bodies northeast of Blackpine Lake, and toward a less well-defined, less
intensely altered centre in the Butler Range at the east border of the map-
area. Thus the processes that produced the Wolverine complex bear no
direct relation to the regional metamorphism of the surrounding rocks.

The changes involved in the development of the Wolverine complex
are essentially those by which quartzites, schists (originally subgreywackes
and greywackes), and limestones are converted into a rock that is identical,
mineralogically and texturally, with a normal igneous granitic rock; the
process is one of granitization (Read, 1943). The granitization has been
accomplished by high-temperature solutions, which circulated mainly along
foliation planes, from which they have intimately pervaded the pores of
the rock itself, have selectively added or subtracted various chemical
constituents, and have facilitated recrystallization and reconstitution of
the material already in the rock. The nature of these solutions, their
ultimate origin, and method of reaction, are fundamental questions in the
entire problem of granitization and the origin of granites, and have given
rise to much controversy and a voluminous literature (Gilluly, 1948, and
numerous references therein). Reynolds (1946) has discussed the sequence
of chemical changes that take place during such a process of granitization;
the changes producing the “Wolverine complex” rocks appear to follow
this sequence quite closely. According to this sequence, the quartzites are
progressively feldspathized, with a marked increase in the alkali content
of the rock, and a somewhat less pronounced enrichment in lime, magnesia,
and iron oxides. The schists are first desilicated, with concomitant increase
of alkali and lime, magnesia, and iron content; at a later stage, when
feldspathization is more advanced, silica is added, and lime, magnesia,
and iron oxides are removed. The limestones are likewise altered in two
stages: first, toward a rock of ultrabasic composition (i.e., amphibolite),
by addition of iron oxide, magnesia, alkalis, and alumina, together with
a subtraction of lime and carbon dioxide; and then the ultrabasic rock
is granitized by addition of silica and alkalis. All of these changes can
be observed in the rocks northeast of Blackpine Lake. It is difficult to
escape the conclusion that the leucogranite is an end product of the
granitization of the Ingenika group sediments, and that, farther northeast,
Tenakihi group rocks are trending toward the same end product.

The grey granodiorite appears to be of a different immediate origin.
Its contact with the sediments, and with the leucogranite supposedly
derived from the sediments, is invariably sharp; and it shows no difference
in character against rocks of different chemical composition. The outward
form of the bodies, and the internal structure as revealed by planes of
foliation, are apparently independent of the structure of the surrounding
rocks. The stocks of grey granodiorite thus appear to have the charac-
teristics of actively intrusive bodies, but there is no evidence that the