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I 
GABBRGS OF EAST SOOKE AND ROCKY POINT. “19 
It is probable that weathering and subsequent erosion have 
removed at least 300 or 400 feet of rock from the top of the 
East Sooke mass. This is inferred from the facts that level dif- 
ferences of some 300 feet are found along the summit line of the 
peninsula, arid that, with the exception of the Maguire anortho- 
site, none of the more acid phases several hundred feet thick 
characteristically occurring about the periphery of the mass is 
found in its interior. If this inference is correct, it is probable 
that a mantle of well weathered material cloaked the surface 
before glaciation; but glaciation has thoroughly removed any 
such mantle and has left the rock surfaces clean and fresh. The 
only positive evidence that still exists to indicate the supposed 
previous condition is the occasional occurrence along the shores 
of Sooke peninsula of vertical dyke-like bands of gabbro 5 to 10 
feet in width, now completely altered to soft kaolinic material, 
but still preserving the original texture of the gabbro and con- 
taining unaltered nodules of it. These seem to have been formed 
by seepage of meteoric water along joint cracks. 
Weathering since glaciation extends only a fraction of an inch 
from the surface in massive rock, and a few inches where joint- 
ing has allowed rain and air to penetrate more rapidly and easily. 
The feldspar has been partly k'aolinized, the augite uralitized, the 
olivine converted to serpentine, and the ilmenite to leucoxene. 
Some of the aplite veins have been epidotized. This is believed 
to be due to meteoric waters and the localization in these veins is 
probably due to the good channels afforded the solutions, and 
perhaps also to the composition and fineness of grain of the 
veins. The feldspars have been completely converted in some 
places to iron-poor varieties of epidote, such as zoisite and clino- 
zoisite, and in places to an iron-poor pistacite. Kaolin has 
usually been formed at the same time, and probably also quartz, 
although any quartz thus formed cannot be separated from the 
quartz originally present. Some aplite dykes were found con- 
sisting wholly of quartz, kaolin, and epidotes, and nearly all have 
undergone this change to a greater or less degree. 
66073 - — A& 
