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map-area, consist of at least 3,000 feet of interbedded golden brown to
silver quartz-muscovite schist, grey to rusty quartz-muscovite-biotite schist
and schistose quartzite, in part garnetiferous, micaceous to nearly pure
granular quartzite, and quartz-biotite-feldspar gneiss. These rocks repre-
sent only the northern part of a large area of similar rocks exposed in the
Butler Range to the east of the map-area. In large part they have a distinc-
tive character due to a more intense metamorphism and alteration than has
affected most of the rocks of the Tenakihi group, and thus they are a part
of the “Wolverine complex” as defined in this report.

STRUCTURAL RELATIONS

The characteristic occurrence of Tenakihi group rocks in the cores
of large anticlinal structures has been noted. Within these major structures,
are structures of lesser size varying to minute crenulations and lineations.

LINEATION

As a whole, the Tenakihi group consists of competent strata, and the
interbedded, strong, micaceous quartzites and tough, but relatively flexible,
quartz-mica schists have facilitated the development of smooth, regular,
asymmetric folds, without noticeable internal fractures, and very few drag-
folds. Local deformation, within individual beds or groups of beds, is,
with a few exceptions, mild in these rocks; and it would seem that even
the smallest structural features show a regional pattern. The most
remarkably uniform of these features is the linear structure developed to
a greater or lesser extent in almost all the Tenakihi group rocks in the
map-area. This lineation is shown by a parallel orientation of lath-like
or splintery grains of mica; by elongated grains or clusters of grains of
quartz; by ‘tails’ of earthy limonitic material strung out behind garnet
porphyroblasts, or in places by strings of the porphyroblasts themselves;
but it is most strikingly manifested in the crumpling, crenulation, and
wrinkling to which the micaceous schists and mica-rich partings in the
quartzites have been subjected. These crenulations vary in size from
minute wrinkles, only clearly visible with the aid of a hand lens, charac-
teristic of the fine-grained schists and phyllites, to small drag-folds 2 to 4
inches from crest to crest, typically found in coarse, flaky, muscovite schist.

Every carefully studied outcrop of Tenakihi group rocks in the map-
area was found to possess lineation to some degree; in a few places in the
Tenakihi Range two distinct directions of lineation could be discerned.
The predominant linear direction is singularly uniform over the entire
exposed area of Tenakihi rocks; a strike of north 20 to 50 degrees west is
maintained with extraordinary fidelity without regard to the present folded
attitudes of the rocks. The plunge of the lineation varies somewhat in
consequence of the deformed schistosity and bedding planes, so that in
most places the lineation lies within the foliation planes of the rock. The
range of plunge of the lineation, however, is not as great as the change in
attitude of the bedding and schistosity surfaces; upon encountering a sharp
fold the elongated mineral grains elsewhere lying in the plane of foliation
may be seen to penetrate that plane and so maintain approximately the
same absolute orientation. The minor crenulations may be observed at
such a point to change from long, parallel, wave-like folds in the schistosity