The Tertiary geology of the Pareora district, South Canterbury

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Abstract
The marine Tertiary rocks in the Pareora district are about 1,500 ft thick and range in age from ?upper Dannevirke Series to Awamoan. They are underlain and overlain conformably by two sets of coal-measures, each about 200 ft thick, but only the lower contains potentially workable lignite seams. The upper coal-measures of probable Southland age are overlain disconiormably or with slight angular unconformity by 600 ft of non-marine, weathered, greywacke gravels (of probable Waitotaran age) which have been folded and faulted together with the underlying Tertiary rocks. These tilted gravels are overlain unconformably by flat-lying, high-level gravels of Pleistocene age. The Tertiary rocks are in fault contact with the greywacke and argillite of the Hunters Hills on the west, the fault having a throw of about 4,000 ft. The little evidence available suggests that this is a reverse fault. Between the Hunters Hills and the sea the Tertiary rocks have been folded into an asymmetrical anticline of which the steep western limb passes into a fault to the north. It is suggested that, because the Waitotaran gravels were deposited while the Kaikoura Orogeny was in progress, they are thickest over the structural lows and thinnest over the structural highs, and that, depending on the amount of erosion prior to their deposition, they may overlie any of the Tertiary formations and possibly even the greywacke undermass.