Geology of the Provinces of Canterbury and Westland, New Zealand : a report comprising the results of official explorations
Igneous Eruptive Rocks
Igneous Eruptive Rocks.
In the lower portion of this zone, on the western declivities of the Central Range, we first find a series of granite veins and dykes of which the oldest were doubtless formed when the crystalline metamorphic formation was uplifted and brought into its present position, the granitic axis to the west being doubtless the main nucleus from which these veins were ejected. The granites are of a great diversity of texture and variety of composition, younger dykes consisting of granites of a different texture, sometimes passing through older ones both being in some instances crossed by still younger greenstone dykes. However, in the upper portion of this extensive formation, I have not met with any eruptive rocks, either on the western slopes of the Southern Alps, or in the district around Lake Wanaka, of which I shall speak next.